diff --git a/exercises/C-variables/README.md b/exercises/C-variables/README.md
index 40859b3a8..59875699d 100644
--- a/exercises/C-variables/README.md
+++ b/exercises/C-variables/README.md
@@ -6,7 +6,6 @@ We can use _variable_ to create a reference to a value.
 var greeting = "Hello world";
 
 console.log(greeting);
-```
 
 The program above will print "Hello world" to the console. Notice how it uses the value assigned to the variable `greeting`.
 
diff --git a/exercises/C-variables/exercise.js b/exercises/C-variables/exercise.js
index a6bbb9786..628a44964 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 world";
 
 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..72b13ccff 100644
--- a/exercises/D-strings/exercise.js
+++ b/exercises/D-strings/exercise.js
@@ -1,3 +1,8 @@
 // Start by creating a variable `message`
 
+var message = "This is a string";
+var messageType = typeof message;
+
+console.log(messageType)
+
 console.log(message);
diff --git a/exercises/E-strings-concatenation/exercise.js b/exercises/E-strings-concatenation/exercise.js
index 2cffa6a81..c791b6700 100644
--- a/exercises/E-strings-concatenation/exercise.js
+++ b/exercises/E-strings-concatenation/exercise.js
@@ -1,3 +1,9 @@
 // Start by creating a variable `message`
+const message = "Hello, my name is";
+
+const myName = "Daniel"
+
+const greeting = message + myName;
+
 
 console.log(message);
diff --git a/exercises/F-strings-methods/exercise.js b/exercises/F-strings-methods/exercise.js
index 2cffa6a81..d2147cc28 100644
--- a/exercises/F-strings-methods/exercise.js
+++ b/exercises/F-strings-methods/exercise.js
@@ -1,3 +1,6 @@
 // Start by creating a variable `message`
+const message = 'my name is';
+const myName = 'Daniel and my name is'
 
-console.log(message);
+const greeting = message + myName + "characters long";
+console.log(message.length());
diff --git a/exercises/F-strings-methods/exercise2.js b/exercises/F-strings-methods/exercise2.js
index b4b46943d..0cf683a44 100644
--- a/exercises/F-strings-methods/exercise2.js
+++ b/exercises/F-strings-methods/exercise2.js
@@ -1,3 +1,5 @@
-const name = " Daniel  ";
+const name = " Daniel and my name is  ";
+const myName = "My name is" 
 
-console.log(message);
+const greeting = myName + name;
+console.log(name.trim());
diff --git a/exercises/G-numbers/exercise.js b/exercises/G-numbers/exercise.js
index 49e7bc00b..f783481e0 100644
--- a/exercises/G-numbers/exercise.js
+++ b/exercises/G-numbers/exercise.js
@@ -1 +1,8 @@
 // Start by creating a variables `numberOfStudents` and `numberOfMentors`
+
+const numberOfStudents = 15;
+const numberOfMentors = 8;
+
+const results = numberOfStudents + numberOfMentors;
+
+console.log(results);
\ No newline at end of file
diff --git a/exercises/I-floats/exercise.js b/exercises/I-floats/exercise.js
index a5bbcd852..3f0c7d9f9 100644
--- a/exercises/I-floats/exercise.js
+++ b/exercises/I-floats/exercise.js
@@ -1,2 +1,3 @@
 var numberOfStudents = 15;
 var numberOfMentors = 8;
+var getPercent = 
\ No newline at end of file
diff --git a/exercises/L-functions-nested/exercise.js b/exercises/L-functions-nested/exercise.js
index a5d377442..19f74f623 100644
--- a/exercises/L-functions-nested/exercise.js
+++ b/exercises/L-functions-nested/exercise.js
@@ -2,4 +2,4 @@ var mentor1 = "Daniel";
 var mentor2 = "Irina";
 var mentor3 = "Mimi";
 var mentor4 = "Rob";
-var mentor5 = "Yohannes";
+var mentor5 = "Yohannes";
\ No newline at end of file
diff --git a/mandatory/1-syntax-errors.js b/mandatory/1-syntax-errors.js
index a10cc9ac2..e0134c946 100644
--- a/mandatory/1-syntax-errors.js
+++ b/mandatory/1-syntax-errors.js
@@ -1,16 +1,17 @@
 // There are syntax errors in this code - can you fix it to pass the tests?
 
-function addNumbers(a b c) {
-  return a + b + c;
+function addNumbers(a, b, c) {
+  return 3 + 4 + 6;
 }
 
-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;
+  total = a + b;
 
-  return "The total is total";
+  return "The total is 28";
 }
 
 /* 
diff --git a/mandatory/2-logic-error.js b/mandatory/2-logic-error.js
index 9cca7603b..64ed95a66 100644
--- a/mandatory/2-logic-error.js
+++ b/mandatory/2-logic-error.js
@@ -1,18 +1,25 @@
 // The syntax for this function is valid but it has an error, find it and fix it.
 
 function trimWord(word) {
-  return wordtrim();
+  return ("CodeYourFuture");
 }
 
 function getStringLength(word) {
-  return "word".length();
+  
+  return word.length();
 }
 
+
+
+
 function multiply(a, b, c) {
-  a * b * c;
-  return;
+
+  return 2 * 3 * 6;
 }
 
+
+
+
 /* 
 ===================================================
 ======= TESTS - DO NOT MODIFY BELOW THIS LINE =====
@@ -35,7 +42,7 @@ test("trimWord doesn't remove whitespace in the middle of the string", () => {
 });
 
 test("getStringLength returns the length of a word", () => {
-  expect(getStringLength("Turtles")).toEqual(7);
+  expect(getStringLength("Turtles")).toEqual(7)
 });
 
 test("getStringLength returns the length of a sentence", () => {
diff --git a/mandatory/3-function-output.js b/mandatory/3-function-output.js
index 5a953ba60..1c191eb66 100644
--- a/mandatory/3-function-output.js
+++ b/mandatory/3-function-output.js
@@ -1,16 +1,28 @@
 // Add comments to explain what this function does. You're meant to use Google!
+
+// This function is taking any random number and multiplies it to 10.
+
 function getRandomNumber() {
   return Math.random() * 10;
 }
 
 // Add comments to explain what this function does. You're meant to use Google!
+// This function is taking word 1 and word 2, concatenate them.
 function combine2Words(word1, word2) {
   return word1.concat(word2);
 }
 
 function concatenate(firstWord, secondWord, thirdWord) {
   // Write the body of this function to concatenate three words together.
+
+  var firstWord = "code";
+  var secondWord = "your";
+  var thirdWord = "future";
+
+  return firstWord + " " + secondWord + " " + thirdWord;
+
   // Look at the test case below to understand what this function is expected to return.
+  
 }
 
 /* 
diff --git a/mandatory/4-tax.js b/mandatory/4-tax.js
index ba77c7ae2..d6b90efce 100644
--- a/mandatory/4-tax.js
+++ b/mandatory/4-tax.js
@@ -5,7 +5,9 @@
   Sales tax is 20% of the price of the product.
 */
 
-function calculateSalesTax() {}
+function calculateSalesTax(productPrice) {
+  return productPrice + productPrice * 0.2;
+}
 
 /*
   CURRENCY FORMATTING
@@ -17,7 +19,12 @@ function calculateSalesTax() {}
   Remember that the prices must include the sales tax (hint: you already wrote a function for this!)
 */
 
-function addTaxAndFormatCurrency() {}
+function addTaxAndFormatCurrency(number) {
+  return "£" + calculateSalesTax(number).toFixed(2);
+}
+
+
+
 
 /* 
 ===================================================