diff --git a/Sprint-3/1-key-implement/1-get-angle-type.js b/Sprint-3/1-key-implement/1-get-angle-type.js
index 08d1f0cbaf..062d43e019 100644
--- a/Sprint-3/1-key-implement/1-get-angle-type.js
+++ b/Sprint-3/1-key-implement/1-get-angle-type.js
@@ -8,8 +8,21 @@
 // Then, write the next test! :) Go through this process until all the cases are implemented
 
 function getAngleType(angle) {
-   if (angle === 90) return "Right angle";
-   // read to the end, complete line 36, then pass your test here
+   if (angle === 90) {
+    return "Right angle";
+   }
+   if (angle === 180) {
+    return "Straight angle";
+   }
+   if (angle < 90) {
+    return "Acute angle";
+   }
+   if (angle < 180) {
+    return "Obtuse angle";
+   }
+   if (angle < 360) {
+    return "Reflex angle";
+   }
 }
 
 // we're going to use this helper function to make our assertions easier to read
@@ -44,13 +57,18 @@ assertEquals(acute, "Acute angle");
 // Then the function should return "Obtuse angle"
 const obtuse = getAngleType(120);
 // ====> write your test here, and then add a line to pass the test in the function above
+assertEquals(obtuse, "Obtuse angle");
 
 // Case 4: Identify Straight Angles:
 // When the angle is exactly 180 degrees,
 // Then the function should return "Straight angle"
 // ====> write your test here, and then add a line to pass the test in the function above
+const straight = getAngleType(180);
+assertEquals(straight, "Straight angle");
 
 // Case 5: Identify Reflex Angles:
 // When the angle is greater than 180 degrees and less than 360 degrees,
 // Then the function should return "Reflex angle"
-// ====> write your test here, and then add a line to pass the test in the function above
\ No newline at end of file
+// ====> write your test here, and then add a line to pass the test in the function above
+const reflex = getAngleType(210);
+assertEquals(reflex, "Reflex angle");
\ No newline at end of file
diff --git a/Sprint-3/1-key-implement/2-is-proper-fraction.js b/Sprint-3/1-key-implement/2-is-proper-fraction.js
index 91583e9413..ed8536f1a1 100644
--- a/Sprint-3/1-key-implement/2-is-proper-fraction.js
+++ b/Sprint-3/1-key-implement/2-is-proper-fraction.js
@@ -8,7 +8,7 @@
 // write one test at a time, and make it pass, build your solution up methodically
 
 function isProperFraction(numerator, denominator) {
-    if (numerator < denominator) return true;
+    return Math.abs(numerator / denominator) < 1;
 }
 
 // here's our helper again
@@ -41,6 +41,7 @@ assertEquals(improperFraction, false);
 // Explanation: The fraction -4/7 is a proper fraction because the absolute value of the numerator (4) is less than the denominator (7). The function should return true.
 const negativeFraction = isProperFraction(-4, 7);
 // ====> complete with your assertion
+assertEquals(negativeFraction, true);
 
 // Equal Numerator and Denominator check:
 // Input: numerator = 3, denominator = 3
@@ -48,6 +49,63 @@ const negativeFraction = isProperFraction(-4, 7);
 // Explanation: The fraction 3/3 is not a proper fraction because the numerator is equal to the denominator. The function should return false.
 const equalFraction = isProperFraction(3, 3);
 // ====> complete with your assertion
+assertEquals(equalFraction, false);
 
 // Stretch:
 // What other scenarios could you test for?
+
+// Negative numerator with absolute value greater than denominator
+// Input: numerator = -5 denominator = 2
+// Target output: false
+// Explanation: The fraction -5/2 is a improper fraction because the absolute value of the numerator (-5) is greater than the denominator (2). The function should return false.
+const negativeGreaterNumerator = isProperFraction(-5, 2);
+assertEquals(negativeGreaterNumerator, false);
+
+// Negative denominator with absolute value greater than numerator
+// Input: numerator = 2 denominator = -5
+// Target output: true
+// Explanation: The fraction 2/-5 is a proper fraction because the numerator (2) is greater than the absolute value of the denominator (-5). The function should return true.
+const negativeGreaterDenominator = isProperFraction(2, -5);
+assertEquals(negativeGreaterDenominator, true);
+
+// Negative denominator with absolute value less than numerator
+// Input: numerator = 5 denominator = -2
+// Target output: false
+// Explanation: The fraction 5/-2 is a improper fraction because the numerator (5) is greater than the absolute value of the denominator (-2). The function should return true.
+const negativeLessDenominator = isProperFraction(5, -2);
+assertEquals(negativeLessDenominator, false);
+
+// Both negative with numerator less in absolute value
+// Input: numerator = -2 denominator = -5
+// Target output: true
+// Explanation: the fraction -2/-5 is a proper fraction because the absolute value of the numerator (-2) less than the absolute value of the denominator (-5).
+const bothNegativeNumeratorLess = isProperFraction(-2, -5);
+assertEquals(bothNegativeNumeratorLess, true);
+
+// Both negative with numerator greater in absolute value
+// Input: numerator = -5 denominator = -2
+// Target output: false
+// Explanation: the fraction -5/-2 is a improper fraction because the absolute value of the numerator(-5) greater than the absolute value of the denominator (-2).
+const bothNegativeNumeratorGreater = isProperFraction(-5, -2);
+assertEquals(bothNegativeNumeratorGreater, false);
+
+// Both negative with equal values
+// Input: numerator = -2 denominator = -2
+// Target output: false
+// Explanation: the fraction -2/-2 is a improper fraction because the numerator(-2) equal to the the denominator (-2).
+const bothNegativeEqual = isProperFraction(-2, -2);
+assertEquals(bothNegativeEqual, false);
+
+// Numerator is zero
+// Input: numerator = 0 denominator = 2
+// Target output: true
+// Explanation: the fraction 0/2 is a proper fraction because the numerator (0) less than the absolute value of the denominator (2).
+const zeroNumerator = isProperFraction(0, 2);
+assertEquals(zeroNumerator, true);
+
+// Denominator is zero
+// Input: numerator = 2 denominator = 0
+// Target output: false
+// Explanation: the fraction 2/0 is a improper fraction because the absolute value of the numerator (2) greater than the denominator (0).
+const zeroDenominator = isProperFraction(2, 0);
+assertEquals(zeroDenominator, false);
\ No newline at end of file
diff --git a/Sprint-3/1-key-implement/3-get-card-value.js b/Sprint-3/1-key-implement/3-get-card-value.js
index aa1cc9f90b..9ad6a5e0a1 100644
--- a/Sprint-3/1-key-implement/3-get-card-value.js
+++ b/Sprint-3/1-key-implement/3-get-card-value.js
@@ -8,7 +8,27 @@
 // write one test at a time, and make it pass, build your solution up methodically
 // just make one change at a time -- don't rush -- programmers are deep and careful thinkers
 function getCardValue(card) {
-    if (rank === "A") return 11;
+  const rank = card.slice(0, card.length - 1);
+  switch (rank) {
+    case "2":
+    case "3":
+    case "4":
+    case "5":
+    case "6":
+    case "7":
+    case "8":
+    case "9":
+      return Number(rank);
+    case "10":
+    case "J":
+    case "Q":
+    case "K":
+      return 10;
+    case "A":
+      return 11;
+    default:
+      throw new Error("Invalid card rank");
+  }
 }
 
 // You need to write assertions for your function to check it works in different cases
@@ -25,27 +45,60 @@ function assertEquals(actualOutput, targetOutput) {
 // Given a card string in the format "A♠" (representing a card in blackjack - the last character will always be an emoji for a suit, and all characters before will be a number 2-10, or one letter of J, Q, K, A),
 // When the function getCardValue is called with this card string as input,
 // Then it should return the numerical card value
-const aceofSpades = getCardValue("A♠");
-assertEquals(aceofSpades, 11);
 
 // Handle Number Cards (2-10):
 // Given a card with a rank between "2" and "9",
 // When the function is called with such a card,
 // Then it should return the numeric value corresponding to the rank (e.g., "5" should return 5).
-const fiveofHearts = getCardValue("5♥");
+const fiveOfHearts = getCardValue("5♥");
+const twoOfHearts = getCardValue("2♥");
+const threeOfHearts = getCardValue("3♥");
+const fourOfHearts = getCardValue("4♥");
+const sixOfHearts = getCardValue("6♥");
+const sevenOfHearts = getCardValue("7♥");
+const eightOfHearts = getCardValue("8♥");
+const nineOfHearts = getCardValue("9♥");
 // ====> write your test here, and then add a line to pass the test in the function above
+assertEquals(fiveOfHearts, 5);
+assertEquals(twoOfHearts, 2);
+assertEquals(threeOfHearts, 3);
+assertEquals(fourOfHearts, 4);
+assertEquals(sixOfHearts, 6);
+assertEquals(sevenOfHearts, 7);
+assertEquals(eightOfHearts, 8);
+assertEquals(nineOfHearts, 9);
 
 // Handle Face Cards (J, Q, K):
 // Given a card with a rank of "10," "J," "Q," or "K",
 // When the function is called with such a card,
 // Then it should return the value 10, as these cards are worth 10 points each in blackjack.
+const tenOfClubs = getCardValue("10♣");
+const jackOfClubs = getCardValue("J♣");
+const queenOfClubs = getCardValue("Q♣");
+const kingOfClubs = getCardValue("K♣");
+assertEquals(tenOfClubs, 10);
+assertEquals(jackOfClubs, 10);
+assertEquals(queenOfClubs, 10);
+assertEquals(kingOfClubs, 10);
 
 // Handle Ace (A):
 // Given a card with a rank of "A",
 // When the function is called with an Ace,
 // Then it should, by default, assume the Ace is worth 11 points, which is a common rule in blackjack.
+const aceOfSpades = getCardValue("A♠");
+assertEquals(aceOfSpades, 11);
 
 // Handle Invalid Cards:
 // Given a card with an invalid rank (neither a number nor a recognized face card),
 // When the function is called with such a card,
 // Then it should throw an error indicating "Invalid card rank."
+
+const oneOfDiamonds = "1♦";
+const twentyUnoOfDiamonds = "21♦";
+const hundredOfDiamonds = "100♦";
+const catOfDiamonds = "C♦";
+
+getCardValue(oneOfDiamonds);
+getCardValue(twentyUnoOfDiamonds);
+getCardValue(hundredOfDiamonds);
+getCardValue(catOfDiamonds);
\ No newline at end of file
diff --git a/Sprint-3/2-mandatory-rewrite/1-get-angle-type.js b/Sprint-3/2-mandatory-rewrite/1-get-angle-type.js
index d61254bd73..5c0033dcc9 100644
--- a/Sprint-3/2-mandatory-rewrite/1-get-angle-type.js
+++ b/Sprint-3/2-mandatory-rewrite/1-get-angle-type.js
@@ -1,7 +1,20 @@
 function getAngleType(angle) {
   if (angle === 90) return "Right angle";
-  // replace with your completed function from key-implement
-
+  if (angle === 90) {
+    return "Right angle";
+  }
+  if (angle === 180) {
+    return "Straight angle";
+  }
+  if (angle < 90) {
+    return "Acute angle";
+  }
+  if (angle < 180) {
+    return "Obtuse angle";
+  }
+  if (angle < 360) {
+    return "Reflex angle";
+  }
 }
 
 
diff --git a/Sprint-3/2-mandatory-rewrite/1-get-angle-type.test.js b/Sprint-3/2-mandatory-rewrite/1-get-angle-type.test.js
index b62827b7c8..65def21dc0 100644
--- a/Sprint-3/2-mandatory-rewrite/1-get-angle-type.test.js
+++ b/Sprint-3/2-mandatory-rewrite/1-get-angle-type.test.js
@@ -1,24 +1,24 @@
 const getAngleType = require("./1-get-angle-type");
 
-test("should identify right angle (90°)", () => {
+test("should identify right angle (angle = 90°)", () => {
   expect(getAngleType(90)).toEqual("Right angle");
 });
 
 // REPLACE the comments with the tests
 // make your test descriptions as clear and readable as possible
 
-// Case 2: Identify Acute Angles:
-// When the angle is less than 90 degrees,
-// Then the function should return "Acute angle"
+test("Should identify acute angles (angle < 90°)", () => {
+  expect(getAngleType(45)).toEqual("Acute angle");
+});
 
-// Case 3: Identify Obtuse Angles:
-// When the angle is greater than 90 degrees and less than 180 degrees,
-// Then the function should return "Obtuse angle"
+test("Should identify obtuse angles (90° < angle < 180°)", () => {
+  expect(getAngleType(120)).toEqual("Obtuse angle");
+});
 
-// Case 4: Identify Straight Angles:
-// When the angle is exactly 180 degrees,
-// Then the function should return "Straight angle"
+test("Should identify straight angle (angle = 180°)", () => {
+  expect(getAngleType(180)).toEqual("Straight angle");
+});
 
-// Case 5: Identify Reflex Angles:
-// When the angle is greater than 180 degrees and less than 360 degrees,
-// Then the function should return "Reflex angle"
+test("Should identify reflex angle (180° < angle < 360°)", () => {
+  expect(getAngleType(210)).toEqual("Reflex angle");
+});
\ No newline at end of file
diff --git a/Sprint-3/2-mandatory-rewrite/2-is-proper-fraction.js b/Sprint-3/2-mandatory-rewrite/2-is-proper-fraction.js
index 9836fe3985..cf91e9d441 100644
--- a/Sprint-3/2-mandatory-rewrite/2-is-proper-fraction.js
+++ b/Sprint-3/2-mandatory-rewrite/2-is-proper-fraction.js
@@ -1,6 +1,5 @@
 function isProperFraction(numerator, denominator) {
-    if (numerator < denominator) return true;
-    // add your completed function from key-implement here
+    return Math.abs(numerator / denominator) < 1;
 }
 
 module.exports = isProperFraction;
\ No newline at end of file
diff --git a/Sprint-3/2-mandatory-rewrite/2-is-proper-fraction.test.js b/Sprint-3/2-mandatory-rewrite/2-is-proper-fraction.test.js
index ff1cc8173c..3ef1fb2cb6 100644
--- a/Sprint-3/2-mandatory-rewrite/2-is-proper-fraction.test.js
+++ b/Sprint-3/2-mandatory-rewrite/2-is-proper-fraction.test.js
@@ -4,8 +4,46 @@ test("should return true for a proper fraction", () => {
   expect(isProperFraction(2, 3)).toEqual(true);
 });
 
-// Case 2: Identify Improper Fractions:
+test("Should return false for improper fraction", () => {
+  expect(isProperFraction(3, 2)).toEqual(false);
+});
+
+test("Should return true for a proper negative fraction", () => {
+  expect(isProperFraction(-2, 3)).toEqual(true);
+});
+
+test("Should return false for equal positive numerator and denominator", () => {
+  expect(isProperFraction(2, 2)).toEqual(false);
+});
+
+test("Should return false for a negative improper fraction", () => {
+  expect(isProperFraction(-3, 2)).toEqual(false);
+});
+
+test("Should return true for a proper fraction with negative denominator", () => {
+  expect(isProperFraction(2, -3)).toEqual(true);
+});
 
-// Case 3: Identify Negative Fractions:
+test("Should return false for an improper fraction with negative denominator", () => {
+  expect(isProperFraction(3, -2)).toEqual(false);  
+});
+
+test("Should return true for a proper fraction with both negative parts", () => {
+  expect(isProperFraction(-2, -3)).toEqual(true);
+});
+
+test("Should return false false for an improper fraction with both negative parts", () => {
+  expect(isProperFraction(-3, -2)).toEqual(false);
+});
+
+test("Should return false for negative equal numerator and denominator", () => {
+  expect(isProperFraction(-2, -2)).toEqual(false);
+});
+
+test("Should return true for a fraction with zero numerator", () => {
+  expect(isProperFraction(0, 2)).toEqual(true);
+});
 
-// Case 4: Identify Equal Numerator and Denominator:
+test("Should return false for a fraction with zero denominator", () => {
+  expect(isProperFraction(2, 0)).toEqual(false);
+});
\ No newline at end of file
diff --git a/Sprint-3/2-mandatory-rewrite/3-get-card-value.js b/Sprint-3/2-mandatory-rewrite/3-get-card-value.js
index 0d95d3736f..703becb2c4 100644
--- a/Sprint-3/2-mandatory-rewrite/3-get-card-value.js
+++ b/Sprint-3/2-mandatory-rewrite/3-get-card-value.js
@@ -1,5 +1,24 @@
 function getCardValue(card) {
-    // replace with your code from key-implement
-    return 11;
+    const rank = card.slice(0, card.length - 1);
+    switch (rank) {
+      case "2":
+      case "3":
+      case "4":
+      case "5":
+      case "6":
+      case "7":
+      case "8":
+      case "9":
+      case "10":
+        return Number(rank);
+      case "J":
+      case "Q":
+      case "K":
+        return 10;
+      case "A":
+        return 11;
+      default:
+        throw new Error("Invalid card rank");
+    }
 }
 module.exports = getCardValue;
\ No newline at end of file
diff --git a/Sprint-3/2-mandatory-rewrite/3-get-card-value.test.js b/Sprint-3/2-mandatory-rewrite/3-get-card-value.test.js
index 03a8e2f341..9d5cf6e974 100644
--- a/Sprint-3/2-mandatory-rewrite/3-get-card-value.test.js
+++ b/Sprint-3/2-mandatory-rewrite/3-get-card-value.test.js
@@ -1,11 +1,90 @@
 const getCardValue = require("./3-get-card-value");
 
-test("should return 11 for Ace of Spades", () => {
-    const aceofSpades = getCardValue("A♠");
-    expect(aceofSpades).toEqual(11);
-    });
-
 // Case 2: Handle Number Cards (2-10):
+test("Should return 2 for Two of Hearts", () => {
+    const twoOfHearts = "2♥";
+    expect(getCardValue(twoOfHearts)).toEqual(2);
+});
+
+test("Should return 3 for Three of Hearts", () => {
+  const threeOfHearts = "3♥";
+  expect(getCardValue(threeOfHearts)).toEqual(3);
+});
+
+test("Should return 4 for Four of Hearts", () => {
+  const fourOfHearts = "4♥";
+  expect(getCardValue(fourOfHearts)).toEqual(4);
+});
+
+test("Should return 5 for Five of Hearts", () => {
+  const fiveOfHearts = "5♥";
+  expect(getCardValue(fiveOfHearts)).toEqual(5);
+});
+
+test("Should return 6 for Six of Hearts", () => {
+  const sixOfHearts = "6♥";
+  expect(getCardValue(sixOfHearts)).toEqual(6);
+});
+
+test("Should return 7 for Seven of Hearts", () => {
+  const sevenOfHearts = "7♥";
+  expect(getCardValue(sevenOfHearts)).toEqual(7);
+});
+
+test("Should return 8 for Eight of Hearts", () => {
+  const eightOfHearts = "8♥";
+  expect(getCardValue(eightOfHearts)).toEqual(8);
+});
+
+test("Should return 9 for Nine of Hearts", () => {
+  const nineOfHearts = "9♥";
+  expect(getCardValue(nineOfHearts)).toEqual(9);
+});
+
+test("Should return 10 for Ten of Hearts", () => {
+  const tenOfClubs = "10♥";
+  expect(getCardValue(tenOfClubs)).toEqual(10);
+});
+
 // Case 3: Handle Face Cards (J, Q, K):
+test("Should return 10 for Jack of Clubs", () => {
+  const jackOfClubs = "J♣";
+  expect(getCardValue(jackOfClubs)).toEqual(10);
+});
+
+test("Should return 10 for Queen of Clubs", () => {
+  const queenOfClubs = "Q♣";
+  expect(getCardValue(queenOfClubs)).toEqual(10);
+});
+
+test("Should return 10 for King of Clubs", () => {
+  const kingOfClubs = "K♣";
+  expect(getCardValue(kingOfClubs)).toEqual(10);
+});
+
 // Case 4: Handle Ace (A):
+test("Should return 11 for Ace of Spades", () => {
+  const aceOfSpades = getCardValue("A♠");
+  expect(aceOfSpades).toEqual(11);
+});
+
 // Case 5: Handle Invalid Cards:
+test("Should throw the 'Invalid card rank' error for One of Diamonds", () => {
+  const oneOfDiamonds = "1♦";
+  expect(() => getCardValue(oneOfDiamonds)).toThrowError("Invalid card rank");
+});
+
+test("Should throw the 'Invalid card rank' error for One of Diamonds", () => {
+  const twentyOneOfDiamonds = "21♦";
+  expect(() => getCardValue(twentyOneOfDiamonds)).toThrowError("Invalid card rank");
+});
+
+test("Should throw the 'Invalid card rank' error for One of Diamonds", () => {
+  const oneHundredOfDiamonds = "100♦";
+  expect(() => getCardValue(oneHundredOfDiamonds)).toThrowError("Invalid card rank");
+});
+
+test("Should throw the 'Invalid card rank' error for One of Diamonds", () => {
+  const catOfDiamonds = "C♦";
+  expect(() => getCardValue(catOfDiamonds)).toThrowError("Invalid card rank");
+});
\ No newline at end of file
diff --git a/Sprint-3/3-mandatory-practice/implement/count.js b/Sprint-3/3-mandatory-practice/implement/count.js
index fce2496501..3c371d4ed4 100644
--- a/Sprint-3/3-mandatory-practice/implement/count.js
+++ b/Sprint-3/3-mandatory-practice/implement/count.js
@@ -1,5 +1,11 @@
 function countChar(stringOfCharacters, findCharacter) {
-    return 5
+    let count = 0;
+    for (let char of stringOfCharacters) {
+        if (char === findCharacter) {
+            count++;
+        }
+    }
+    return count;
 }
 
 module.exports = countChar;
\ No newline at end of file
diff --git a/Sprint-3/3-mandatory-practice/implement/count.test.js b/Sprint-3/3-mandatory-practice/implement/count.test.js
index 42baf4b4b0..2c1c032e2c 100644
--- a/Sprint-3/3-mandatory-practice/implement/count.test.js
+++ b/Sprint-3/3-mandatory-practice/implement/count.test.js
@@ -22,3 +22,10 @@ test("should count multiple occurrences of a character", () => {
 // And a character char that does not exist within the case-sensitive str,
 // When the function is called with these inputs,
 // Then it should return 0, indicating that no occurrences of the char were found in the case-sensitive str.
+
+test("Should return 0 for string without the searching character", () => {
+  const str = "AAAAA";
+  const char = "a";
+  const count = countChar(str, char);
+  expect(count).toEqual(0);
+});
diff --git a/Sprint-3/3-mandatory-practice/implement/get-ordinal-number.js b/Sprint-3/3-mandatory-practice/implement/get-ordinal-number.js
index 24f528b0d3..1cfb230c19 100644
--- a/Sprint-3/3-mandatory-practice/implement/get-ordinal-number.js
+++ b/Sprint-3/3-mandatory-practice/implement/get-ordinal-number.js
@@ -1,5 +1,42 @@
 function getOrdinalNumber(num) {
- return "1st";
+  if (typeof num !== "number") {
+    throw new TypeError(`'${num}' is not a number.`);
+  }
+
+  if (!Number.isInteger(num)) {
+    throw new RangeError(`'${num}' is float`);
+  }
+
+  if (num < 1) {
+    throw new RangeError(`'${num}' is not natural number`);
+  }
+
+  const lastDigit = num % 10;
+  const last2Digits = num % 100;
+  
+  console.log(`${num} ${lastDigit} ${last2Digits}`);
+  if (lastDigit === 1) {
+    if (last2Digits === 11) {
+      return num + "th";
+    }
+    return num + "st";
+  }
+  
+  if (lastDigit === 2) {
+    if (last2Digits === 12) {
+      return num + "th";
+    }
+    return num + "nd";
+  }
+  
+  if (lastDigit === 3) {
+    if (last2Digits === 13) {
+      return num + "th";
+    }
+    return num + "rd";
+  }
+  
+  return num + "th";
 }
 
 module.exports = getOrdinalNumber;
\ No newline at end of file
diff --git a/Sprint-3/3-mandatory-practice/implement/get-ordinal-number.test.js b/Sprint-3/3-mandatory-practice/implement/get-ordinal-number.test.js
index 6d55dfbb40..700f2546e6 100644
--- a/Sprint-3/3-mandatory-practice/implement/get-ordinal-number.test.js
+++ b/Sprint-3/3-mandatory-practice/implement/get-ordinal-number.test.js
@@ -4,10 +4,131 @@ const getOrdinalNumber = require("./get-ordinal-number");
 // continue testing and implementing getOrdinalNumber for additional cases
 // Write your tests using Jest - remember to run your tests often for continual feedback
 
-// Case 1: Identify the ordinal number for 1
-// When the number is 1,
-// Then the function should return "1st"
+// Case 1: Identify the ordinal for numbers ending in 1. Should return ordinals ending in '1st'
+// except numbers ending in 11 for which should return ordinals ending in '11th'
 
-test("should return '1st' for 1", () => {
-    expect(getOrdinalNumber(1)).toEqual("1st");
-    });
+test("Should return '1st' for 1", () => {
+  expect(getOrdinalNumber(1)).toEqual("1st");
+});
+
+test("Should return '11th' for 11", () => {
+  expect(getOrdinalNumber(11)).toEqual("11th");
+})
+
+test("Should return '21st' for 21", () => {
+  expect(getOrdinalNumber(21)).toEqual("21st");
+});
+
+test("Should return '101st' for 101", () => {
+  expect(getOrdinalNumber(101)).toEqual("101st");
+});
+
+test("Should return '111th' for 111", () => {
+  expect(getOrdinalNumber(111)).toEqual("111th");
+});
+
+test("Should return '121st' for 121", () => {
+  expect(getOrdinalNumber(121)).toEqual("121st");
+});
+
+// Case 2: Identify the ordinal for numbers ending in 2. Should return ordinals ending in '2nd'
+// except numbers ending in 12 for which should return ordinals ending in '12th'
+
+test("Should return '2nd' for 2", () => {
+  expect(getOrdinalNumber(2)).toEqual("2nd");
+});
+
+test("Should return '12th' for 12", () => {
+  expect(getOrdinalNumber(12)).toEqual("12th");
+});
+
+test("Should return '22nd' for 22", () => {
+  expect(getOrdinalNumber(22)).toEqual("22nd");
+});
+
+test("Should return '102nd' for 102", () => {
+  expect(getOrdinalNumber(102)).toEqual("102nd");
+});
+
+test("Should return '112th' for 112", () => {
+  expect(getOrdinalNumber(112)).toEqual("112th");
+});
+
+test("Should return '122nd' for 122", () => {
+  expect(getOrdinalNumber(122)).toEqual("122nd");
+});
+
+// Case 3: Identify the ordinal for numbers ending in 3. Should return ordinals ending in '3rd'
+// except numbers ending in 13 for which should return ordinals ending in '13th'
+
+test("Should return '3rd' for 3", () => {
+  expect(getOrdinalNumber(3)).toEqual("3rd");
+});
+
+test("Should return '13th' for 13", () => {
+  expect(getOrdinalNumber(13)).toEqual("13th");
+});
+
+test("Should return '23rd' for 23", () => {
+  expect(getOrdinalNumber(23)).toEqual("23rd");
+});
+
+test("Should return '103rd' for 103", () => {
+  expect(getOrdinalNumber(103)).toEqual("103rd");
+});
+
+test("Should return '113th' for 113", () => {
+  expect(getOrdinalNumber(113)).toEqual("113th");
+});
+
+test("Should return '123rd' for 123", () => {
+  expect(getOrdinalNumber(123)).toEqual("123rd");
+});
+
+// Case 3: Identify the ordinal for numbers ending in 4 to 0. Should return ordinals ending in 'th'.
+
+test("Should return '4th' for 4", () => {
+  expect(getOrdinalNumber(4)).toEqual("4th");
+});
+
+test("Should return '15th' for 15", () => {
+  expect(getOrdinalNumber(15)).toEqual("15th");
+});
+
+test("Should return '26th' for 26", () => {
+  expect(getOrdinalNumber(26)).toEqual("26th");
+});
+
+test("Should return '107th' for 107", () => {
+  expect(getOrdinalNumber(107)).toEqual("107th");
+});
+
+test("Should return '288th' for 288", () => {
+  expect(getOrdinalNumber(288)).toEqual("288th");
+});
+
+test("Should return '1039th' for 1039", () => {
+  expect(getOrdinalNumber(1039)).toEqual("1039th");
+});
+
+//Case 4: Identify invalid type of argument.
+
+test("Should throw TypeError if num is not Number", () => {
+  expect(() => {getOrdinalNumber("10")}).toThrow();
+});
+
+//Case 5: Identify float argument.
+
+test("Should throw RangeError if num is float", () => {
+  expect(() => {getOrdinalNumber(2.71)}).toThrow();
+});
+
+//Case 6: Identify non natural argument
+
+test("Should throw Range error for 0", () => {
+  expect(() => {getOrdinalNumber(0)}).toThrow();
+});
+
+test("Should throw Range error for negative num", () => {
+  expect(() => {getOrdinalNumber(-1);}).toThrow();
+});
\ No newline at end of file
diff --git a/Sprint-3/3-mandatory-practice/implement/repeat.js b/Sprint-3/3-mandatory-practice/implement/repeat.js
index 621f9bd35b..28e67af671 100644
--- a/Sprint-3/3-mandatory-practice/implement/repeat.js
+++ b/Sprint-3/3-mandatory-practice/implement/repeat.js
@@ -1,5 +1,5 @@
-function repeat() {
-    return "hellohellohello";
+function repeat(stringToRepeat, repeatCount) {
+    return stringToRepeat.repeat(repeatCount);
 }
 
 module.exports = repeat;
\ No newline at end of file
diff --git a/Sprint-3/3-mandatory-practice/implement/repeat.test.js b/Sprint-3/3-mandatory-practice/implement/repeat.test.js
index 8a4ab42efc..822bb93a00 100644
--- a/Sprint-3/3-mandatory-practice/implement/repeat.test.js
+++ b/Sprint-3/3-mandatory-practice/implement/repeat.test.js
@@ -21,12 +21,32 @@ test("should repeat the string count times", () => {
 // When the repeat function is called with these inputs,
 // Then it should return the original str without repetition, ensuring that a count of 1 results in no repetition.
 
+test("Should return the original string for count = 1", () => {
+    const str = "hello";
+    const count = 1;
+    const repeatedString = repeat(str, count);
+    expect(repeatedString).toEqual(str);
+});
+
 // case: Handle Count of 0:
 // Given a target string str and a count equal to 0,
 // When the repeat function is called with these inputs,
 // Then it should return an empty string, ensuring that a count of 0 results in an empty output.
 
+test("Should return empty string for count = 0", () => {
+    const str = "hello";
+    const count = 0;
+    const repeatedString = repeat(str, count);
+    expect(repeatedString).toEqual("");
+})
+
 // case: Negative Count:
 // Given a target string str and a negative integer count,
 // When the repeat function is called with these inputs,
 // Then it should throw an error or return an appropriate error message, as negative counts are not valid.
+
+test("Should throw a Range error for a negative count", () => {
+    const str = "hello";
+    const count = -1;
+    expect(() => {repeat(str, count)}).toThrow();
+});
\ No newline at end of file
diff --git a/Sprint-3/4-stretch-investigate/card-validator.js b/Sprint-3/4-stretch-investigate/card-validator.js
new file mode 100644
index 0000000000..507ac5e92d
--- /dev/null
+++ b/Sprint-3/4-stretch-investigate/card-validator.js
@@ -0,0 +1,35 @@
+function cardValidator(cardNumber) {
+  //checking the card number length
+  if (cardNumber.length !== 16) {
+    return false;
+  }
+
+  const digitsRegEx = /\d/;
+  const lastChar = cardNumber[cardNumber.length - 1];
+
+  //checking the card number last character is even digit
+  if (digitsRegEx.test(lastChar) && Number(lastChar) % 2 != 0) {
+    return false;
+  }
+
+  let digitsSum = 0;
+  
+  for (let i = 0; i < cardNumber.length; i++) {
+    const currentChar = cardNumber[i];
+    //checking all the card number characters are digits
+    if (!digitsRegEx.test(currentChar)) {
+      return false;
+    }
+    //summing digits of the card number
+    digitsSum += Number(currentChar);
+  }
+  //checking sum of digits of the card number
+  if (digitsSum < 16) {
+    return false;
+  }
+  //returning true if all checks passed
+  return true;
+}
+
+
+module.exports = cardValidator;
\ No newline at end of file
diff --git a/Sprint-3/4-stretch-investigate/card-validator.test.js b/Sprint-3/4-stretch-investigate/card-validator.test.js
new file mode 100644
index 0000000000..42318c1037
--- /dev/null
+++ b/Sprint-3/4-stretch-investigate/card-validator.test.js
@@ -0,0 +1,29 @@
+const isValidCard = require("./card-validator");
+
+test("Card number should be 16 characters length.", () => {
+  const cardNumber = "000044440000222";
+  const targetOutput = isValidCard(cardNumber);
+
+  expect(targetOutput).toBe(false);
+})
+
+test("Card number should not contains non-digit characters", () => {
+  const cardNumber = "000044440000a222";
+  const targetOutput = isValidCard(cardNumber);
+
+  expect(targetOutput).toBe(false);
+});
+
+test("Sum of the card number digits should not be less than 16", () => {
+  const cardNumber = "0000111100002222";
+  const targetOutput = isValidCard(cardNumber);
+
+  expect(targetOutput).toBe(false);
+})
+
+test("Card number should ends in even digit", () => {
+  const cardNumber = "0000444400002221";
+  const targetOutput = isValidCard(cardNumber);
+
+  expect(targetOutput).toBe(false);
+})
\ No newline at end of file
diff --git a/Sprint-3/4-stretch-investigate/find.js b/Sprint-3/4-stretch-investigate/find.js
index c7e79a2f21..4b7e7ab87f 100644
--- a/Sprint-3/4-stretch-investigate/find.js
+++ b/Sprint-3/4-stretch-investigate/find.js
@@ -20,6 +20,14 @@ console.log(find("code your future", "z"));
 // Pay particular attention to the following:
 
 // a) How the index variable updates during the call to find
+// In the begin of function after the declaration the index variable initialize with value 0.
+// Then in the end of the every iteration of the while loop it increased by 1.
+
 // b) What is the if statement used to check
+// The if statement checks the value of the index variable exceeds the string last character iindex.
+
 // c) Why is index++ being used?
+// Because we the while loop without a counter instead of a for loop with the known count of iteration.
+
 // d) What is the condition index < str.length used for?
+// This condition indicate reaching of the end of the given string and exiting from the while loop.
diff --git a/Sprint-3/4-stretch-investigate/password-validator.js b/Sprint-3/4-stretch-investigate/password-validator.js
index b55d527dba..9932fbb917 100644
--- a/Sprint-3/4-stretch-investigate/password-validator.js
+++ b/Sprint-3/4-stretch-investigate/password-validator.js
@@ -1,6 +1,42 @@
-function passwordValidator(password) {
-    return password.length < 5 ? false : true
-}
+function passwordValidator(password, previousPasswords) {
+    for (let i = 0; i < previousPasswords.length; i++) {
+      const currentPreviousPassword = previousPasswords[i];
+
+      if (password === currentPreviousPassword) {
+        return false
+      }
 
+    }
+    if (password.length < 5) {
+        return false;
+    }
+
+    const uppercaseLettersRegEx = /[A-Z]/;
+    const lowercaseLettersRegEx = /[a-z]/;
+    const digitsRegEx = /[0-9]/;
+    const nonAlphanumericSymbolsRegEx = /[!#\$%\.\*&]/;
+    let hasUppercaseLetter = false;
+    let hasLowercaseLetter = false
+    let hasDigit = false;
+    let hasNonAlphanumericSymbol = false;
+    
+    for (let i = 0; i < password.length; i++) {
+    const currentSymbol = password[i];
+      if (uppercaseLettersRegEx.test(currentSymbol)) {
+        hasUppercaseLetter = true;
+      }
+      if (lowercaseLettersRegEx.test(currentSymbol)) {
+        hasLowercaseLetter = true;
+      }
+      if (digitsRegEx.test(currentSymbol)) {
+        hasDigit = true;
+      }
+      if (nonAlphanumericSymbolsRegEx.test(currentSymbol)) {
+        hasNonAlphanumericSymbol = true;
+      }  
+    }
+    return hasUppercaseLetter && hasLowercaseLetter && hasDigit && hasNonAlphanumericSymbol;
+}
 
+passwordValidator("Bcd1$", ["Bcd1$"]);
 module.exports = passwordValidator;
\ No newline at end of file
diff --git a/Sprint-3/4-stretch-investigate/password-validator.test.js b/Sprint-3/4-stretch-investigate/password-validator.test.js
index 8fa3089d6b..aaa1dce379 100644
--- a/Sprint-3/4-stretch-investigate/password-validator.test.js
+++ b/Sprint-3/4-stretch-investigate/password-validator.test.js
@@ -15,12 +15,48 @@ To be valid, a password must:
 You must breakdown this problem in order to solve it. Find one test case first and get that working
 */
 const isValidPassword = require("./password-validator");
-test("password has at least 5 characters", () => {
-    // Arrange
-    const password = "12345";
-    // Act
-    const result = isValidPassword(password);
-    // Assert
-    expect(result).toEqual(true);
-}
-);
\ No newline at end of file
+const previousPasswords = ["Bcd1$"];
+
+test("Password should have at least 5 characters", () => {
+  // Arrange
+  const password = "Ab1$";
+  // Act
+  const targetOutput = isValidPassword(password, previousPasswords);
+  // Assert
+  expect(targetOutput).toBe(false);
+});
+
+test("Password should have at least 1 English uppercase letter", () => {
+  const password = "abc1#";
+  const targetOutput = isValidPassword(password, previousPasswords);
+
+  expect(targetOutput).toBe(false);
+});
+
+test("Password should have at least 1 English lowercase letter", () => {
+  const password = "ABC1&";
+  const targetOutput = isValidPassword(password, previousPasswords);
+
+  expect(targetOutput).toBe(false);
+});
+
+test("Password should have at least 1 digit", () => {
+  const password = "Abcd*";
+  const targetOutput = isValidPassword(password, previousPasswords);
+
+  expect(targetOutput).toBe(false);
+})
+
+test("Password should have at least 1 non-alphanumeric symbol ('!', '#', '$', '%', '.', '*', '&')", () => {
+  const password = "Abcd1";
+  const targetOutput = isValidPassword(password, previousPasswords);
+
+  expect(targetOutput).toBe(false);
+})
+
+test("Password should not be in previous passwords array", () => {
+  const password = "Bcd1$";
+  const targetOutput = isValidPassword(password, previousPasswords);
+
+  expect(targetOutput).toBe(false);
+});
\ No newline at end of file