diff --git a/exercises/B-hello-world/exercise.js b/exercises/B-hello-world/exercise.js
index b179ee953..cd4cc12ac 100644
--- a/exercises/B-hello-world/exercise.js
+++ b/exercises/B-hello-world/exercise.js
@@ -1 +1 @@
-console.log("Hello world");
+console.log( 1 ,"Hello azadeh", 12.4, 'bye');
diff --git a/exercises/C-variables/exercise.js b/exercises/C-variables/exercise.js
index a6bbb9786..82bbbb600 100644
--- a/exercises/C-variables/exercise.js
+++ b/exercises/C-variables/exercise.js
@@ -1,3 +1,8 @@
 // Start by creating a variable `greeting`
+let greeting = "Hello Azadeh"
 
+
+
+console.log(greeting);
+console.log(greeting);
 console.log(greeting);
diff --git a/exercises/D-strings/exercise.js b/exercises/D-strings/exercise.js
index 2cffa6a81..73c4745bf 100644
--- a/exercises/D-strings/exercise.js
+++ b/exercises/D-strings/exercise.js
@@ -1,3 +1,5 @@
 // Start by creating a variable `message`
+const message = "this is a string";
 
 console.log(message);
+console.log(typeof message);
diff --git a/exercises/E-strings-concatenation/exercise.js b/exercises/E-strings-concatenation/exercise.js
index 2cffa6a81..9e8e55914 100644
--- a/exercises/E-strings-concatenation/exercise.js
+++ b/exercises/E-strings-concatenation/exercise.js
@@ -1,3 +1,5 @@
 // Start by creating a variable `message`
-
+const greetingStart = 'hello , I am ';
+const myName = 'Azadeh'
+const message= greetingStart + myName;
 console.log(message);
diff --git a/exercises/F-strings-methods/exercise.js b/exercises/F-strings-methods/exercise.js
index 2cffa6a81..abfc45277 100644
--- a/exercises/F-strings-methods/exercise.js
+++ b/exercises/F-strings-methods/exercise.js
@@ -1,3 +1,7 @@
 // Start by creating a variable `message`
-
+const myName="Azadeh";
+const intro = "My name is";
+const message =  intro + " " + myName + " "+ "and my name is "+ myName.length + " characters long ";
 console.log(message);
+
+
diff --git a/exercises/F-strings-methods/exercise2.js b/exercises/F-strings-methods/exercise2.js
index b4b46943d..1fc4b2747 100644
--- a/exercises/F-strings-methods/exercise2.js
+++ b/exercises/F-strings-methods/exercise2.js
@@ -1,3 +1,6 @@
-const name = " Daniel  ";
-
+const name = " Daniel  ".trim();
+const intro = "My name is";
+const message =  intro + " " + name + " "+ "and my name is "+ name.length + " characters long ";
 console.log(message);
+
+
diff --git a/exercises/G-numbers/exercise.js b/exercises/G-numbers/exercise.js
index 49e7bc00b..06711a5d5 100644
--- a/exercises/G-numbers/exercise.js
+++ b/exercises/G-numbers/exercise.js
@@ -1 +1,11 @@
 // Start by creating a variables `numberOfStudents` and `numberOfMentors`
+const numberOfMentors = 5;
+const numberOfStudents = 30;
+const mentorsNum = "Number of mentors: "+ numberOfMentors;
+const studentNum = "Number of students: " + numberOfStudents;
+const totalNum = "Total number of students and mentors:" + (numberOfMentors + numberOfStudents);
+
+
+console.log(mentorsNum);
+console.log(studentNum);
+console.log (totalNum);
diff --git a/exercises/I-floats/exercise.js b/exercises/I-floats/exercise.js
index a5bbcd852..57faebe0e 100644
--- a/exercises/I-floats/exercise.js
+++ b/exercises/I-floats/exercise.js
@@ -1,2 +1,14 @@
-var numberOfStudents = 15;
-var numberOfMentors = 8;
+const numberOfStudents = 15;
+const numberOfMentors = 8;
+const totalNumber = numberOfMentors+numberOfStudents;
+
+
+const percentageOfMentors =  (numberOfMentors/totalNumber)*100 ;
+const percentageOfStudents = (numberOfStudents/totalNumber)*100 ;
+const roundPercentageOfMentors = "Percentage Mentors:" + Math.round( percentageOfMentors) +"%";
+const roundPercentageOfStudents = "Percentage students:" + Math.round( percentageOfStudents)+"%";
+
+console.log( roundPercentageOfMentors);
+console.log(roundPercentageOfStudents);
+
+
diff --git a/exercises/J-functions/README.md b/exercises/J-functions/README.md
index 22105ca2a..142736657 100644
--- a/exercises/J-functions/README.md
+++ b/exercises/J-functions/README.md
@@ -13,7 +13,7 @@ a) _call_ it with an input and
 b) assign the returned value to a variable
 
 ```js
-var result = double(2);
+var result = double();
 
 console.log(result); // 4
 ```
diff --git a/exercises/J-functions/exercise.js b/exercises/J-functions/exercise.js
index 0ae5850e5..e7278f7bd 100644
--- a/exercises/J-functions/exercise.js
+++ b/exercises/J-functions/exercise.js
@@ -1,5 +1,5 @@
 function halve(number) {
-  // complete the function here
+  return number / 2;
 }
 
 var result = halve(12);
diff --git a/exercises/J-functions/exercise2.js b/exercises/J-functions/exercise2.js
index 82ef5e780..468d45596 100644
--- a/exercises/J-functions/exercise2.js
+++ b/exercises/J-functions/exercise2.js
@@ -1,5 +1,6 @@
 function triple(number) {
   // complete function here
+  return number * 3;
 }
 
 var result = triple(12);
diff --git a/exercises/K-functions-parameters/exercise.js b/exercises/K-functions-parameters/exercise.js
index 8d5db5e69..7b3b584bf 100644
--- a/exercises/K-functions-parameters/exercise.js
+++ b/exercises/K-functions-parameters/exercise.js
@@ -1,5 +1,6 @@
 // Complete the function so that it takes input parameters
-function multiply() {
+function multiply( a , b ) {
+  return a * b;
   // Calculate the result of the function and return it
 }
 
diff --git a/exercises/K-functions-parameters/exercise2.js b/exercises/K-functions-parameters/exercise2.js
index db7a8904b..e366146b2 100644
--- a/exercises/K-functions-parameters/exercise2.js
+++ b/exercises/K-functions-parameters/exercise2.js
@@ -1,5 +1,7 @@
 // Declare your function first
-
+function divide(a,b){
+    return a/b;
+}
 var result = divide(3, 4);
 
 console.log(result);
diff --git a/exercises/K-functions-parameters/exercise3.js b/exercises/K-functions-parameters/exercise3.js
index 537e9f4ec..fbfbf0c9b 100644
--- a/exercises/K-functions-parameters/exercise3.js
+++ b/exercises/K-functions-parameters/exercise3.js
@@ -1,4 +1,7 @@
 // Write your function here
+function createGreeting(name){
+    return "Hello, my name is " + name;
+}
 
 var greeting = createGreeting("Daniel");
 
diff --git a/exercises/K-functions-parameters/exercise4.js b/exercises/K-functions-parameters/exercise4.js
index 7ab44589e..7b3e0e59a 100644
--- a/exercises/K-functions-parameters/exercise4.js
+++ b/exercises/K-functions-parameters/exercise4.js
@@ -1,5 +1,8 @@
 // Declare your function first
-
+function adds(a , b){
+    return a + b;
+}
+var sum = adds(13 , 124);
 // Call the function and assign to a variable `sum`
 
 console.log(sum);
diff --git a/exercises/K-functions-parameters/exercise5.js b/exercises/K-functions-parameters/exercise5.js
index 7c5bcd605..f9cc2ecae 100644
--- a/exercises/K-functions-parameters/exercise5.js
+++ b/exercises/K-functions-parameters/exercise5.js
@@ -1,5 +1,8 @@
 // Declare your function here
-
+function createLongGreeting (name,age){
+    return "Hello, my name is " + name + " and I am " + age +" years old";
+}
 const greeting = createLongGreeting("Daniel", 30);
 
 console.log(greeting);
+
diff --git a/exercises/L-functions-nested/exercise.js b/exercises/L-functions-nested/exercise.js
index a5d377442..06d00071f 100644
--- a/exercises/L-functions-nested/exercise.js
+++ b/exercises/L-functions-nested/exercise.js
@@ -3,3 +3,23 @@ var mentor2 = "Irina";
 var mentor3 = "Mimi";
 var mentor4 = "Rob";
 var mentor5 = "Yohannes";
+ function upperCaseName ( mentor ){
+ return mentor.toUpperCase( )
+ }
+ function greeting( hi,name){
+    const mentor = upperCaseName(name)
+    return hi.concat( mentor)
+ }
+ const printName1= greeting("Hello ",mentor1);
+ const printName2= greeting("Hello " ,mentor2);
+ const printName3= greeting("Hello " ,mentor3);
+ const printName4= greeting("Hello " ,mentor4);
+ const printName5= greeting("Hello " ,mentor5);
+ console.log (printName1);
+ console.log (printName2);
+ console.log (printName3);
+ console.log (printName4);
+ console.log (printName5);
+
+
+ 
\ No newline at end of file
diff --git a/extra/1-currency-conversion.js b/extra/1-currency-conversion.js
index 75b3c6aab..a33504be2 100644
--- a/extra/1-currency-conversion.js
+++ b/extra/1-currency-conversion.js
@@ -5,7 +5,9 @@
   Write a function that converts a price to USD (exchange rate is 1.4 $ to £)
 */
 
-function convertToUSD() {}
+function convertToUSD( pound ) {
+  return pound * 1.4;
+}
 
 /*
   CURRENCY CONVERSION
@@ -15,7 +17,10 @@ function convertToUSD() {}
   They have also decided that they should add a 1% fee to all foreign transactions, which means you only convert 99% of the £ to BRL.
 */
 
-function convertToBRL() {}
+function convertToBRL(pound) {
+  let brl = pound * 5.7 ;
+  return Number( ( brl - (brl * (1 / 100)) ).toFixed(2) );  
+}
 
 /* ======= TESTS - DO NOT MODIFY ===== 
 There are some Tests in this file that will help you work out if your code is working.
diff --git a/extra/2-piping.js b/extra/2-piping.js
index b4f8c4c1b..32ac774c9 100644
--- a/extra/2-piping.js
+++ b/extra/2-piping.js
@@ -16,26 +16,28 @@
   the final result to the variable goodCode
 */
 
-function add() {
-
+function add( a ,b ) {
+  return a + b; 
 }
 
-function multiply() {
-
+function multiply(a , b) {
+return a * b;
 }
 
-function format() {
-
-}
+function format( number) {
+return `£${number}`;
+//"# "+number;
+} 
 
 const startingValue = 2;
 
 // Why can this code be seen as bad practice? Comment your answer.
-let badCode =
+let badCode = "£"+((startingValue+10 )*2);
 
 /* BETTER PRACTICE */
 
-let goodCode =
+let goodCode = format( multiply( add( startingValue ,10 ) ,2 ) )
+
 
 /* ======= TESTS - DO NOT MODIFY ===== 
 There are some Tests in this file that will help you work out if your code is working.
diff --git a/extra/3-magic-8-ball.js b/extra/3-magic-8-ball.js
index 46f65f928..e86e50516 100644
--- a/extra/3-magic-8-ball.js
+++ b/extra/3-magic-8-ball.js
@@ -43,10 +43,50 @@
     Very doubtful.
 */
 
+// This should log "The ball has shaken!"
+// and return the answer.
+
+const veryNegativeAnswers = [
+  "Don't count on it.",
+  'My reply is no.',
+  'My sources say no.',
+  'Outlook not so good.',
+  'Very doubtful.',
+];
+const negativeAnswers = [
+  'Reply hazy, try again.',
+  'Ask again later.',
+  'Better not tell you now.',
+  'Cannot predict now.',
+  'Concentrate and ask again.',
+];
+const positiveAnswers = [
+  'As I see it, yes.',
+  'Most likely.',
+  'Outlook good.',
+  'Yes.',
+  'Signs point to yes.',
+];
+const veryPositiveAnswers = [
+  'You may rely on it',
+  'You may rely on it',
+  'It is decidedly so.',
+  'It is certain.',
+];
+const possibleAnswers = veryNegativeAnswers.concat(
+  negativeAnswers,
+  positiveAnswers,
+  veryPositiveAnswers
+);
 // This should log "The ball has shaken!"
 // and return the answer.
 function shakeBall() {
   //Write your code in here
+  const randomIndex = Math.floor(Math.random() * possibleAnswers.length);
+  const randomAnswer = possibleAnswers[randomIndex];
+  const message = 'The ball has shaken!';
+  console.log(message);
+  return randomAnswer;
 }
 
 /* 
@@ -55,11 +95,14 @@ function shakeBall() {
     - positive
     - negative
     - very negative
-
   This function should expect to be called with any value which was returned by the shakeBall function.
 */
 function checkAnswer(answer) {
-  //Write your code in here
+  const answerIndex = possibleAnswers.indexOf(answer);
+  if (answerIndex >= 15) return 'very positive';
+  if (answerIndex >= 10) return 'positive';
+  if (answerIndex >= 5) return 'negative';
+  return 'very negative';
 }
 
 /* 
@@ -76,12 +119,12 @@ To run the tests for just this one file, type `npm test -- --testPathPattern 3-m
 test("whole magic 8 ball sequence", () => {
   const consoleLogSpy = jest.spyOn(global.console, "log");
   const answer = shakeBall();
-
+ 
   expect(typeof answer).toEqual("string");
 
   expect(consoleLogSpy).toHaveBeenCalledTimes(1);
   expect(consoleLogSpy).toHaveBeenLastCalledWith("The ball has shaken!");
-
+ 
   expect(checkAnswer(answer)).toBeOneOf([
     "very positive",
     "positive",
diff --git a/mandatory/1-syntax-errors.js b/mandatory/1-syntax-errors.js
index a10cc9ac2..4957a5f12 100644
--- a/mandatory/1-syntax-errors.js
+++ b/mandatory/1-syntax-errors.js
@@ -1,16 +1,16 @@
 // There are syntax errors in this code - can you fix it to pass the tests?
 
-function addNumbers(a b c) {
+function addNumbers(a,b,c) {
   return a + b + c;
 }
 
-function introduceMe(name, age)
-  return "Hello, my name is " + name "and I am " age + "years old";
-
+function introduceMe(name, age){
+  return "Hello, my name is " + name + " and I am " + age + " years old";
+}
 function getTotal(a, b) {
-  total = a ++ b;
+  const total = a + b;
 
-  return "The total is total";
+  return "The total is " + total;
 }
 
 /* 
diff --git a/mandatory/2-logic-error.js b/mandatory/2-logic-error.js
index 9cca7603b..a566ec60f 100644
--- a/mandatory/2-logic-error.js
+++ b/mandatory/2-logic-error.js
@@ -1,16 +1,17 @@
 // The syntax for this function is valid but it has an error, find it and fix it.
-
+function wordtrim(str) {
+  return str.trim(str)
+}
 function trimWord(word) {
-  return wordtrim();
+  return wordtrim(word);
 }
 
 function getStringLength(word) {
-  return "word".length();
+  return word.length;
 }
 
 function multiply(a, b, c) {
-  a * b * c;
-  return;
+  return  a * b * c;
 }
 
 /* 
diff --git a/mandatory/3-function-output.js b/mandatory/3-function-output.js
index 5a953ba60..8be755201 100644
--- a/mandatory/3-function-output.js
+++ b/mandatory/3-function-output.js
@@ -1,9 +1,11 @@
 // Add comments to explain what this function does. You're meant to use Google!
+// The Math.random() function returns a floating-point, pseudo-random number in the range 0 to less than 1 (inclusive of 0, but not 1) with approximately uniform distribution over that range — which you can then scale to your desired range. The implementation selects the initial seed to the random number generation algorithm; it cannot be chosen or reset by the user.
 function getRandomNumber() {
   return Math.random() * 10;
 }
 
 // Add comments to explain what this function does. You're meant to use Google!
+//  concatanetion two words to each other
 function combine2Words(word1, word2) {
   return word1.concat(word2);
 }
@@ -11,6 +13,8 @@ function combine2Words(word1, word2) {
 function concatenate(firstWord, secondWord, thirdWord) {
   // Write the body of this function to concatenate three words together.
   // Look at the test case below to understand what this function is expected to return.
+  // return firstWord +" " + secondWord + " "+thirdWord
+  return `${firstWord} ${secondWord} ${thirdWord}`
 }
 
 /* 
diff --git a/mandatory/4-tax.js b/mandatory/4-tax.js
index ba77c7ae2..1e3d1308b 100644
--- a/mandatory/4-tax.js
+++ b/mandatory/4-tax.js
@@ -5,7 +5,10 @@
   Sales tax is 20% of the price of the product.
 */
 
-function calculateSalesTax() {}
+function calculateSalesTax(price) {
+  const tax = price *20/100
+  return tax + price
+}
 
 /*
   CURRENCY FORMATTING
@@ -17,7 +20,11 @@ function calculateSalesTax() {}
   Remember that the prices must include the sales tax (hint: you already wrote a function for this!)
 */
 
-function addTaxAndFormatCurrency() {}
+function addTaxAndFormatCurrency(price) {
+  const tax = price *20/100
+  const total= tax+ price
+  return `£${total.toFixed(2)}`
+}
 
 /* 
 ===================================================
diff --git a/package.json b/package.json
index 93e0861e3..ec1719365 100644
--- a/package.json
+++ b/package.json
@@ -14,15 +14,21 @@
     "url": "https://github.com/CodeYourFuture/JavaScript-Core-1-Coursework-Week1/issues"
   },
   "jest": {
-    "setupFilesAfterEnv": ["jest-extended"],
+    "setupFilesAfterEnv": [
+      "jest-extended"
+    ],
     "projects": [
       {
         "displayName": "mandatory",
-        "testMatch": ["<rootDir>/mandatory/*.js"]
+        "testMatch": [
+          "<rootDir>/mandatory/*.js"
+        ]
       },
       {
         "displayName": "extra",
-        "testMatch": ["<rootDir>/extra/*.js"]
+        "testMatch": [
+          "<rootDir>/extra/*.js"
+        ]
       }
     ]
   },
@@ -30,5 +36,8 @@
   "devDependencies": {
     "jest": "^26.6.3",
     "jest-extended": "^0.11.5"
+  },
+  "dependencies": {
+    "expect": "^29.0.3"
   }
 }