diff --git a/README.md b/README.md
index 408612117c..b93d0dad30 100644
--- a/README.md
+++ b/README.md
@@ -30,14 +30,36 @@ Edit this document to include your answers after each question. Make sure to lea
 
 1. Describe the biggest difference between `.forEach` & `.map`.
 
+The .map method stores return values and returns a new array.
+The .forEach method throws away return values and will mutate the current array.
+
+
 2. What is the difference between a function and a method?
 
+A function performs a task or calculates a value.
+A method IS a function that is the property of an object.
+
+
 3. What is closure?
 
+Closure is a function and all of its lexical environment.
+
 4. Describe the four rules of the 'this' keyword.
 
+1.	Global Binding
+When in the global scope, the value of “this” will be the window/console Object;
+2.	 Implicit Binding 
+       Whenever a function is called by a method inside of an object, the object left of the dot gets ‘this’.
+3.	 New Binding
+ Whenever a constructor function is used, ‘this’ refers to the specific instance of the object that is created and returned by the constructor function.
+4.	 Explicit Binding
+ Whenever JavaScript’s call or apply method is used, ‘this’ is explicitly defined.
+
+
 5. Why do we need super() in an extended class?
 
+The super() keyword illuminates the need for the parent call inside the constructor and automatically binds the parent to the child.
+
 ## Project Set up
 
 Follow these steps to set up and work on your project:
diff --git a/challenges/classes.js b/challenges/classes.js
index 992e39dc0b..4d54bb3b7d 100644
--- a/challenges/classes.js
+++ b/challenges/classes.js
@@ -1,7 +1,38 @@
 // 1. Copy and paste your prototype in here and refactor into class syntax.
-
+class CuboidMaker2 {
+    constructor(length, width, height) {
+        this.length = length;
+        this.width = width;
+        this.height = height;
+    }
+    volume() {
+        return this.length * this.width * this.height;
+    }
+    surfaceArea() {
+        return ((this.length * this.width) + (this.length * this.height) + (this.width * this.height)) * 2;
+    }
+}
+class Cuboid2 extends CuboidMaker2 {
+    constructor(length, width, height) {
+        super(length, width, height)
+    }
+}
+let squared = new Cuboid2(4, 5, 5);
 // Test your volume and surfaceArea methods by uncommenting the logs below:
-// console.log(cuboid.volume()); // 100
-// console.log(cuboid.surfaceArea()); // 130
+console.log(squared.volume()); // 100
+console.log(squared.surfaceArea()); // 130
 
-// Stretch Task: Extend the base class CuboidMaker with a sub class called CubeMaker.  Find out the formulas for volume and surface area for cubes and create those methods using the dimension properties from CuboidMaker.  Test your work by logging out your volume and surface area.
\ No newline at end of file
+// Stretch Task: Extend the base class CuboidMaker with a sub class called CubeMaker.  Find out the formulas for volume and surface area for cubes and create those methods using the dimension properties from CuboidMaker.  Test your work by logging out your volume and surface area.
+// class CubeMaker extends CuboidMaker2 {
+//     constructor(length, width, height) {
+//         super(length, width, height)
+//         this.length = length;
+//         this.width = width;
+//         this.height = height;
+//     }
+//     surfaceArea() {
+//         return (this.length * this.width) * 6;
+//     }
+// }
+// console.log(CubeMaker.volume(5, 5, 5));
+// console.log(CubeMaker.surfaceArea(5, 5));
\ No newline at end of file
diff --git a/challenges/functions.js b/challenges/functions.js
index 6e3688bfcc..21624f0d0a 100644
--- a/challenges/functions.js
+++ b/challenges/functions.js
@@ -6,6 +6,9 @@
   * The last parameter accepts a callback
   * The consume function should return the invocation of cb, passing a and b into cb as arguments
 */
+function consume(a, b, cb) {
+  return cb(a, b);
+}
 
 
 /* Step 2: Create several functions to callback with consume();
@@ -13,17 +16,27 @@
   * Create a function named multiply that returns the product of two numbers 
   * Create a function named greeting that accepts a first and last name and returns "Hello first-name last-name, nice to meet you!"
 */
+function add(a, b) {
+  return a + b;
+}
+function multiply(a, b) {
+  return a * b;
+}
+function greeting(a, b) {
+  return `Hello ${a + b}, nice to meet you!`;
+}
 
 
 /* Step 3: Check your work by un-commenting the following calls to consume(): */
-// console.log(consume(2, 2, add)); // 4
-// console.log(consume(10, 16, multiply)); // 160
-// console.log(consume("Mary", "Poppins", greeting)); // Hello Mary Poppins, nice to meet you!
+console.log(consume(2, 2, add)); // 4
+console.log(consume(10, 16, multiply)); // 160
+console.log(consume("Mary", "Poppins", greeting)); // Hello Mary Poppins, nice to meet you!
 
 
 // ==== Closures ==== 
 
 // Explain in your own words why nestedfunction can access the variable internal.
+// Since the nestedFunction is nested inside the myFunction, both nestedFunction and variable internal are in the same function scope which makes it possible to access one another
 
 // Explanation: 
 
diff --git a/challenges/objects-arrays.js b/challenges/objects-arrays.js
index 86970b0c29..e6b3d12463 100644
--- a/challenges/objects-arrays.js
+++ b/challenges/objects-arrays.js
@@ -5,6 +5,32 @@
   Use this pattern to create your objects: 
   object name, diet, weight, length, period
 */
+let tRex = {
+  name: 'tyrannosaurus',
+  diet: 'carnivorous',
+  weight: '7000 kg',
+  length: '12 m',
+  period: 'Late Cretaceous',
+  roar: function roar() {
+    return `RAWERSRARARWERSARARARRRR!`;
+  }
+}
+
+let steg = {
+  name: 'stegosaurus',
+  diet: 'herbivorous',
+  weight: '2000 kg',
+  length: '9 m',
+  period: 'Late Jurassic',
+}
+
+let velo = {
+  name: 'velociraptor',
+  diet: 'carnivorous',
+  weight: '15 kg',
+  length: '1.8 m',
+  period: 'Late Cretaceous',
+}
 
 // tyrannosaurus, carnivorous, 7000kg, 12m, Late Cretaceous
 
@@ -15,20 +41,20 @@
 // Using your dinosaur objects, log answers to these questions:
 
 // How much did tyrannosaurus weigh?
-console.log();
+console.log(tRex.weight);
 
 // What was the diet of a velociraptor?
-console.log();
+console.log(velo.diet);
 
 // How long was a stegosaurus?
-console.log();
+console.log(steg.length);
 
 // What time period did tyrannosaurus live in?
-console.log();
+console.log(tRex.period);
 
 
 // Create a new roar method for the tyrannosaurus.  When called, return "RAWERSRARARWERSARARARRRR!" Log the result.
-console.log();
+console.log(tRex.roar());
 
 
 // ==== Arrays ====
@@ -50,24 +76,26 @@ const graduates = [
 
 /* Request 1: Create a new array called universities that contains all the universities in the graduates array. This will be an array of strings.
 
+
 Once you have the new array created, log the result. */
 const universities = [];
+let gradUniversities = graduates.filter(graduates => universities.push(graduates.university));
 console.log(universities);
 
 /* Request 2: Create a new array called contactInfo that contains both first name and email of each student. This will be an array of strings.
-
 The resulting contact information strings should have a space between the first name and the email, like this: 
 "Josh josh@example.com"
 
 Log the result of your new array. */
 const contactInfo = [];
+let conacts = graduates.forEach(graduates => contactInfo.push(graduates.first_name + " " + graduates.email));
 console.log(contactInfo);
 
 /* Request 3: Find out how many universities have the string "Uni" included in their name. Create a new array called unisWithUni that contains them all. This will be an array of objects. Log the result. */
 const unisWithUni = [];
-console.log(unisWithUni);
-
+graduates.forEach(graduates => { graduates.university.includes('Uni') ? unisWithUni.push(graduates.university) : false });
 
+console.log(unisWithUni);
 // ==== ADVANCED Array Methods ====
 
 // Given this zoo data from around the United States, follow the instructions below.  Use the specific array methods in the requests below to solve the problems.
@@ -91,6 +119,7 @@ The zoos want to display both the scientific name and the animal name in front o
 
 */
 const displayNames = [];
+zooAnimals.forEach(zooAnimals => { displayNames.push(zooAnimals.animal_name + ", " + zooAnimals.scientific_name) });
 console.log(displayNames);
 
 /* Request 2: .map()
@@ -100,6 +129,7 @@ The zoos need a list of all their animal's names (animal_name only) converted to
 */
 
 const lowCaseAnimalNames = [];
+zooAnimals.map(zooAnimals => { lowCaseAnimalNames.push(zooAnimals.animal_name.toLowerCase()) });
 console.log(lowCaseAnimalNames);
 
 /* Request 3: .filter() 
@@ -108,6 +138,7 @@ The zoos are concerned about animals with a lower population count. Using filter
 
 */
 const lowPopulationAnimals = [];
+zooAnimals.filter(zooAnimals => { (zooAnimals.population < 5) ? lowPopulationAnimals.push(zooAnimals.animal_name) : false });
 console.log(lowPopulationAnimals);
 
 /* Request 4: .reduce() 
@@ -115,7 +146,9 @@ console.log(lowPopulationAnimals);
 The zoos need to know their total animal population across the United States. Find the total population from all the zoos using the .reduce() method. Remember the reduce method takes two arguments: a callback (which itself takes two args), and an initial value for the count.
 
 */
-const populationTotal = 0;
+const populationTotal = zooAnimals.reduce((accumulator, currentIndex) => {
+  return accumulator += currentIndex.population
+}, 0);
 console.log(populationTotal);
 
 
diff --git a/challenges/prototypes.js b/challenges/prototypes.js
index 4cafc33e95..06a0087dbb 100644
--- a/challenges/prototypes.js
+++ b/challenges/prototypes.js
@@ -6,28 +6,41 @@
   Create a constructor function named CuboidMaker that accepts properties for length, width, and height
 */
 
+function CuboidMaker(length, width, height) {
+  this.length = length;
+  this.width = width;
+  this.height = height;
+}
+
 
 /* == Step 2: Volume Method ==
   Create a method using CuboidMaker's prototype that returns the volume of a given cuboid's length, width, and height
-  
+
   Formula for cuboid volume: length * width * height
 */
+CuboidMaker.prototype.volume = function (length, width, height) {
+  return this.length * this.width * this.height;
+}
 
 
 /* == Step 3: Surface Area Method ==
-  Create another method using CuboidMaker's prototype that returns the surface area of a given cuboid's length, width, and height. 
+  Create another method using CuboidMaker's prototype that returns the surface area of a given cuboid's length, width, and height.
 
   Formula for cuboid surface area of a cube: 2 * (length * width + length * height + width * height)
 */
+CuboidMaker.prototype.surfaceArea = function (length, width, height) {
+  return ((this.length * this.width) + (this.length * this.height) + (this.width * this.height)) * 2;
+}
 
 
 /* == Step 4: Create a new object that uses CuboidMaker ==
   Create a cuboid object that uses the new keyword to use our CuboidMaker constructor
-  Add properties and values of length: 4, width: 5, and height: 5 to cuboid.   
+  Add properties and values of length: 4, width: 5, and height: 5 to cuboid.
 */
+const cuboid = new CuboidMaker(4, 5, 5);
 
 // Test your volume and surfaceArea methods by uncommenting the logs below:
-// console.log(cuboid.volume()); // 100
-// console.log(cuboid.surfaceArea()); // 130
+console.log(cuboid.volume()); // 100
+console.log(cuboid.surfaceArea()); // 130