diff --git a/src/functions-and-arrays.js b/src/functions-and-arrays.js
index 3a7dbec41..80ae385ad 100644
--- a/src/functions-and-arrays.js
+++ b/src/functions-and-arrays.js
@@ -1,24 +1,72 @@
 // Iteration #1: Find the maximum
-function maxOfTwoNumbers() {}
+function maxOfTwoNumbers(a, b) {
+  if (a>b){
+    return a ;
+  } else {
+    return b ;
+  }
+}
 
+console.log(maxOfTwoNumbers(100, 20))
 
 
 // Iteration #2: Find longest word
 const words = ['mystery', 'brother', 'aviator', 'crocodile', 'pearl', 'orchard', 'crackpot'];
 
-function findLongestWord() {}
+function findLongestWord(arr) {
+  let longestWord = arr[0]
+  if (arr.length === 0 ) {return null}
+  else {
+  for (let i = 0; i<arr.length; i++){
+    if (arr[i].length > longestWord.length){
+      longestWord = arr[i]
+    } 
+  }
+  return longestWord
+  }
+}
+
+let empty = ["apple"]
+let result = findLongestWord(empty)
+console.log(result)
 
 
 
 // Iteration #3: Calculate the sum
 const numbers = [6, 12, 1, 18, 13, 16, 2, 1, 8, 10];
 
-function sumNumbers() {}
-
+function sumNumbers(arr) {
+  let addition = 0
+  for (let i = 0; i<arr.length; i++){
+    addition += arr[i]    
+  }
+  return addition
+}
+console.log(sumNumbers(numbers))
 
 
 // Iteration #3.1 Bonus:
-function sum() {}
+
+const mixedArr = [6, 12, 'miami', 1, true, 'barca', '200', 'lisboa', 8, 10];
+// should return: 57
+
+function sum(arr) {
+  let addition = 0
+  for (let i = 0; i<arr.length; i++){
+    if (typeof arr[i] === 'number'){
+      addition += arr[i]
+    } else if (typeof arr[i] === 'boolean') {
+      addition += arr[i]
+    } else if (typeof arr[i] === 'string') {
+      addition += arr[i].length
+    } else {
+      throw new Error('Error message goes here');
+    }    
+  }  
+  return addition
+}
+
+console.log(mixedArr)
 
 
 
@@ -26,16 +74,63 @@ function sum() {}
 // Level 1: Array of numbers
 const numbersAvg = [2, 6, 9, 10, 7, 4, 1, 9];
 
-function averageNumbers() {}
+function averageNumbers(arr) {
+  if (arr.length === 0){
+    return null
+  }
+  let addition = 0
+  for (let i = 0; i < arr.length; i++){
+    addition += arr[i]    
+  }
+  return addition / arr.length
+}
+
+let emptyAvg = []
+console.log(avg(empty))
+console.log(avg(numbersAvg))
 
 
 // Level 2: Array of strings
 const wordsArr = ['seat', 'correspond', 'linen', 'motif', 'hole', 'smell', 'smart', 'chaos', 'fuel', 'palace'];
 
-function averageWordLength() { }
+function averageWordLength(arr) {
+  if (arr.length === 0){return null}
+  let addition = 0
+  for (let i = 0; i < arr.length; i++){
+  addition += arr[i].length    
+  }
+  return addition / arr.length  
+}
+console.log(averageWordLength(wordsArr))
 
 // Bonus - Iteration #4.1
-function avg() {}
+
+const mixedArr2 = [6, 12, 'miami', 1, true, 'barca', '200', 'lisboa', 8, 10];
+
+// should return: 5.7
+
+function avg(arr) {
+  if (arr.length === 0){return null}
+  let addition = 0
+  for (let i = 0; i<arr.length; i++){
+    if (typeof arr[i] === 'number'){
+      addition += arr[i]
+    } else if (typeof arr[i] === 'boolean') {
+      addition += arr[i]
+    } else if (typeof arr[i] === 'string') {
+      addition += arr[i].length
+    } else {
+      throw new Error('Error message goes here');
+    }    
+  }  
+  return addition / arr.length
+}
+
+console.log(mixedArr2)
+
+
+
+
 
 // Iteration #5: Unique arrays
 const wordsUnique = [
@@ -52,14 +147,36 @@ const wordsUnique = [
   'bring'
 ];
 
-function uniquifyArray() {}
-
+function uniquifyArray(arr) {
+  if (arr.length === 0){
+    return null;
+  } else {
+  let uniqueWords = [arr[0]];
+  for( let i = 0; i< arr.length; i++){
+    if(uniqueWords.includes(arr[i])){
+      continue
+    } else{
+      uniqueWords.push(arr[i])
+    }
+  }
+  return uniqueWords
+  }  
+}
+console.log(uniquifyArray(wordsUnique))
 
 
 // Iteration #6: Find elements
 const wordsFind = ['machine', 'subset', 'trouble', 'starting', 'matter', 'eating', 'truth', 'disobedience'];
 
-function doesWordExist() {}
+function doesWordExist(arr, word) {
+  if (arr.length === 0){
+    return null
+  } else {
+  return arr.includes(word);
+  }
+}
+
+console.log(doesWordExist(wordsFind, 'dog'))
 
 
 
@@ -78,7 +195,22 @@ const wordsCount = [
   'matter'
 ];
 
-function howManyTimes() {}
+function howManyTimes(arr, word) {
+  if (arr.length === 0){
+    return 0;
+  } else {
+    let counter = 0 ;
+    arr.forEach((item) => {
+      if (item === word){
+        counter += 1
+      }
+    })
+    return counter
+  }        
+}  
+
+console.log(howManyTimes(wordsCount, 'matter'))
+