diff --git a/exercises/B-hello-world/exercise.js b/exercises/B-hello-world/exercise.js
index b179ee953..5c93f6a64 100644
--- a/exercises/B-hello-world/exercise.js
+++ b/exercises/B-hello-world/exercise.js
@@ -1 +1,4 @@
 console.log("Hello world");
+console.log("Hello Guys, I am learning JavaScript")
+console.log (Hello)
+console.log(1000)
\ No newline at end of file
diff --git a/exercises/C-variables/exercise.js b/exercises/C-variables/exercise.js
index a6bbb9786..b9370bd64 100644
--- a/exercises/C-variables/exercise.js
+++ b/exercises/C-variables/exercise.js
@@ -1,3 +1,6 @@
 // Start by creating a variable `greeting`
 
+var greeting = "Hello Everyone"
+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..1442feed6 100644
--- a/exercises/D-strings/exercise.js
+++ b/exercises/D-strings/exercise.js
@@ -1,3 +1,6 @@
 // Start by creating a variable `message`
-
+var message = "Hello"
+var messageType = typeof message;
 console.log(message);
+console.log(messageType);
+
diff --git a/exercises/E-strings-concatenation/exercise.js b/exercises/E-strings-concatenation/exercise.js
index 2cffa6a81..5620e7609 100644
--- a/exercises/E-strings-concatenation/exercise.js
+++ b/exercises/E-strings-concatenation/exercise.js
@@ -1,3 +1,6 @@
 // Start by creating a variable `message`
+var greetingStart = "Hello, my name is "
+var name = "Niamh"
 
-console.log(message);
+var greeting = greetingStart + name;
+console.log(greeting);
diff --git a/exercises/F-strings-methods/exercise.js b/exercises/F-strings-methods/exercise.js
index 2cffa6a81..a82192a3e 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`
+var name = "Niamh";
+
+var nameLength = name.length;
+
+console.log(nameLength)
 
-console.log(message);
diff --git a/exercises/G-numbers/exercise.js b/exercises/G-numbers/exercise.js
index 49e7bc00b..d17f63a98 100644
--- a/exercises/G-numbers/exercise.js
+++ b/exercises/G-numbers/exercise.js
@@ -1 +1,7 @@
 // Start by creating a variables `numberOfStudents` and `numberOfMentors`
+var numberOfStudents = 50;
+var numberOfMentors = 10;
+
+var sum = numberOfStudents + numberOfMentors;
+
+console.log(sum);
diff --git a/exercises/I-floats/exercise.js b/exercises/I-floats/exercise.js
index a5bbcd852..49433c80f 100644
--- a/exercises/I-floats/exercise.js
+++ b/exercises/I-floats/exercise.js
@@ -1,2 +1,6 @@
 var numberOfStudents = 15;
 var numberOfMentors = 8;
+
+var percentageOfStudents = 15 /23 * 100; 
+var percentageOfMentors = 8/23*100; 
+
diff --git a/exercises/J-functions/exercise.js b/exercises/J-functions/exercise.js
index 0ae5850e5..ab14837ed 100644
--- a/exercises/J-functions/exercise.js
+++ b/exercises/J-functions/exercise.js
@@ -1,7 +1,8 @@
 function halve(number) {
   // complete the function here
+  return number / 2;
 }
 
-var result = halve(12);
+var result = halve(10000100101010);
 
 console.log(result);
diff --git a/exercises/J-functions/exercise2.js b/exercises/J-functions/exercise2.js
index 82ef5e780..d78dd00c0 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..a4eed9d76 100644
--- a/exercises/K-functions-parameters/exercise.js
+++ b/exercises/K-functions-parameters/exercise.js
@@ -1,6 +1,7 @@
 // Complete the function so that it takes input parameters
-function multiply() {
+function multiply(num1, num2) {
   // Calculate the result of the function and return it
+  return num1 * num2;
 }
 
 // Assign the result of calling the function the variable `result`
diff --git a/exercises/K-functions-parameters/exercise2.js b/exercises/K-functions-parameters/exercise2.js
index db7a8904b..ff8703696 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 (num1, num2){
+    return num1/num2;
+}
 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..583abc089 100644
--- a/exercises/K-functions-parameters/exercise3.js
+++ b/exercises/K-functions-parameters/exercise3.js
@@ -1,5 +1,7 @@
 // Write your function here
-
+fucntion greeting(name){
+    return `Hello my name is ${name}`;
+}
 var greeting = createGreeting("Daniel");
 
 console.log(greeting);
diff --git a/exercises/K-functions-parameters/exercise4.js b/exercises/K-functions-parameters/exercise4.js
index 7ab44589e..3c7891699 100644
--- a/exercises/K-functions-parameters/exercise4.js
+++ b/exercises/K-functions-parameters/exercise4.js
@@ -1,5 +1,10 @@
 // Declare your function first
+function add(num1, num2) {
+    return num1 + num2;
+}
 
 // Call the function and assign to a variable `sum`
+const sum = add(13, 200)
+
 
 console.log(sum);
diff --git a/exercises/K-functions-parameters/exercise5.js b/exercises/K-functions-parameters/exercise5.js
index 7c5bcd605..e1ecbffce 100644
--- a/exercises/K-functions-parameters/exercise5.js
+++ b/exercises/K-functions-parameters/exercise5.js
@@ -1,5 +1,9 @@
 // Declare your function here
 
+function createGreeting(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..69f986554 100644
--- a/exercises/L-functions-nested/exercise.js
+++ b/exercises/L-functions-nested/exercise.js
@@ -3,3 +3,14 @@ var mentor2 = "Irina";
 var mentor3 = "Mimi";
 var mentor4 = "Rob";
 var mentor5 = "Yohannes";
+
+function shoutGreeting (name){
+    name = name.toUpperCase();
+    console.log(`Hello ${name}`);
+}
+
+shoutGreeting(mentor1);
+shoutGreeting(mentor2);
+shoutGreeting(mentor3);
+shoutGreeting(mentor4);
+shoutGreeting(mentor5);
\ No newline at end of file
diff --git a/mandatory/1-syntax-errors.js b/mandatory/1-syntax-errors.js
index a10cc9ac2..679ab353a 100644
--- a/mandatory/1-syntax-errors.js
+++ b/mandatory/1-syntax-errors.js
@@ -1,6 +1,6 @@
 // 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;
 }
 
@@ -8,9 +8,9 @@ function introduceMe(name, age)
   return "Hello, my name is " + name "and I am " age + "years old";
 
 function getTotal(a, b) {
-  total = a ++ b;
+  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..d896984bc 100644
--- a/mandatory/2-logic-error.js
+++ b/mandatory/2-logic-error.js
@@ -1,16 +1,16 @@
 // The syntax for this function is valid but it has an error, find it and fix it.
 
 function trimWord(word) {
-  return wordtrim();
+  return word.trim();
 }
 
 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..12c414151 100644
--- a/mandatory/3-function-output.js
+++ b/mandatory/3-function-output.js
@@ -1,16 +1,19 @@
-// Add comments to explain what this function does. You're meant to use Google!
+// Get a random number and times by 10
 function getRandomNumber() {
   return Math.random() * 10;
 }
 
 // Add comments to explain what this function does. You're meant to use Google!
 function combine2Words(word1, word2) {
-  return word1.concat(word2);
+     const firstWord = word1.concat(" ", word2);
+  return firstWord ;
 }
 
 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.
+   const result = firstWord.concat(" ", secondWord, " ", thirdWord);
+  return result ;
 }
 
 /* 
diff --git a/mandatory/4-tax.js b/mandatory/4-tax.js
index ba77c7ae2..f52224a1a 100644
--- a/mandatory/4-tax.js
+++ b/mandatory/4-tax.js
@@ -4,8 +4,9 @@
   A business requires a program that calculates how much the price of a product is including sales tax
   Sales tax is 20% of the price of the product.
 */
-
-function calculateSalesTax() {}
+function calculateSalesTax(price) {
+  return price * 1.2;
+}
 
 /*
   CURRENCY FORMATTING
@@ -17,7 +18,9 @@ function calculateSalesTax() {}
   Remember that the prices must include the sales tax (hint: you already wrote a function for this!)
 */
 
-function addTaxAndFormatCurrency() {}
+function addTaxAndFormatCurrency(prices) {
+  return "£" + calculateSalesTax(prices).toFixed(2);
+}
 
 /* 
 ===================================================
diff --git a/package.json b/package.json
index 58555936d..2083b7060 100644
--- a/package.json
+++ b/package.json
@@ -2,10 +2,12 @@
   "name": "javascript-core-1-coursework-week1",
   "version": "1.0.0",
   "description": "Exercises for JS1 Week 1",
+}
+ {
   "scripts": {
-    "test": "jest --testRegex='mandatory[/\\\\].*\\.js$'",
-    "extra-tests": "jest --testRegex='extra[/\\\\].*\\.js$'"
-  },
+    "test": "jest"
+  }
+}
   "repository": {
     "type": "git",
     "url": "git+https://github.com/CodeYourFuture/JavaScript-Core-1-Coursework-Week1.git"
@@ -14,7 +16,9 @@
     "url": "https://github.com/CodeYourFuture/JavaScript-Core-1-Coursework-Week1/issues"
   },
   "jest": {
-    "setupFilesAfterEnv": ["jest-extended"]
+    "setupFilesAfterEnv": [
+      "jest-extended"
+    ]
   },
   "homepage": "https://github.com/CodeYourFuture/JavaScript-Core-1-Coursework-Week1#readme",
   "devDependencies": {