diff --git a/brainTeasers/waterJugs.md b/brainTeasers/waterJugs.md
index 5276fc0..e740359 100644
--- a/brainTeasers/waterJugs.md
+++ b/brainTeasers/waterJugs.md
@@ -1 +1,12 @@
 You have a five-quart jug, a three-quart jug, and an unlimited supply of water (but no measuring cups). How would you come up with exactly four quarts of water? Note that the jugs are oddly shaped, such that filling up exactly "half" of the jug would be impossible.
+
+5 Quart | 3 Quart
+------------------
+    0   |   3
+    3   |   0
+    3   |   3
+    5   |   1
+    0   |   1
+    1   |   0
+    1   |   3
+    4   |   0
\ No newline at end of file
diff --git a/callBackPractice/callBackPractice.js b/callBackPractice/callBackPractice.js
index 8f5d9ac..3501f69 100644
--- a/callBackPractice/callBackPractice.js
+++ b/callBackPractice/callBackPractice.js
@@ -20,24 +20,31 @@
 
 const foods = ['pineapple', 'mango', 'ribeye', 'curry', 'tacos', 'ribeye', 'mango'];
 
+const firstItem = (arr, cb) => cb(arr[0]);
+
 firstItem(foods, (firstItem) => {
   console.log(`The first item is ${firstItem}.`);
 });
 
 // Write a function called getLength that passes the length of the array into the callback
 
+const getLength = (arr, cb) => cb(arr.length);
+
 getLength(foods, (length) => {
   console.log(`The length of the array is ${length}.`);
 });
 
 // Write a function called last which passes the last item of the array into the callback
 
+const last = (arr, cb) => cb(arr[arr.length - 1]);
+
 last(foods, (lastItem) => {
   console.log(`The last item in the array is ${lastItem}.`);
 });
 
 // Write a function called sumNums that adds two numbers and passes the result to the callback
 
+const sumNums = (num1, num2, cb) => cb(num1 + num2);
 
 sumNums(5, 10, (sum) => {
   console.log(`The sum is ${sum}.`);
@@ -45,6 +52,8 @@ sumNums(5, 10, (sum) => {
 
 // Write a function called multiplyNums that adds two numbers and passes the result to the callback
 
+const multiplyNums= (num1, num2, cb) => cb(num1 * num2);
+
 multiplyNums(5, 10, (product) => {
   console.log(`The product is ${product}.`);
 });
@@ -52,6 +61,14 @@ multiplyNums(5, 10, (product) => {
 // Write a function called contains that checks if an item is present inside of the given array.
 // Pass true to the callback if it is, otherwise pass false
 
+const contains = (arr, item, cb) => {
+  for (let i = 0; i < arr.length; i++) {
+    if (arr[i] === item);
+    return cb(true);
+  }
+  return cb(false);
+};
+
 contains(foods, 'ribeye', (result) => {
   console.log(result ? 'ribeye is in the array' : 'ribeye is not in the array');
 });
@@ -59,12 +76,27 @@ contains(foods, 'ribeye', (result) => {
 // Write a function called removeDuplicates that removes all duplicate values from the given array.
 // Pass the array to the callback function.  Do not mutate the original array.
 
+const removeDuplicates = (arr, cb) => {
+  const newArr = [];
+  for (let i = 0; i < arr.length; i++) {
+    if (!(newArr.includes(arr[i]))) {
+      newArr.push(arr[i]);
+    }
+  }
+  cb(newArr);
+};
+
 removeDuplicates(foods, (uniqueFoods) => {
   console.log(`foods with duplicates removed: ${uniqueFoods}`);
 });
 
 // Write a function called forEach that iterates over the provided array and passes the value and index into the callback.
 
+const forEach = (arr, cb) => {
+  for (let i = 0; i < arr.length; i++) {
+    cb(arr[i], i);
+  }
+};
 
 forEach(foods, (value, index) => {
   console.log(`${value} is at index ${index}.`);
diff --git a/commonCharacters/commonCharacters.js b/commonCharacters/commonCharacters.js
index ec31d82..ac64433 100644
--- a/commonCharacters/commonCharacters.js
+++ b/commonCharacters/commonCharacters.js
@@ -6,3 +6,16 @@
  * Example: commonCharacters('acexivou', 'aegihobu')  *
  * Returns: 'aeiou'
 */
+
+const commonCharacters = (str1, str2) => {
+  let common = [];
+
+  str1.split('').forEach((char) => {
+    if (str2.split('').includes(char) && !common.includes(char)) {
+      common.push(char);
+    }
+  })
+  return common.join('').replace(' ', '');
+}
+
+console.log(commonCharacters('abcdefg', 'bcd g'));
\ No newline at end of file
diff --git a/evenOccurences/evenOccurences.js b/evenOccurences/evenOccurences.js
index 1943998..13f27ec 100644
--- a/evenOccurences/evenOccurences.js
+++ b/evenOccurences/evenOccurences.js
@@ -10,6 +10,19 @@
  *    * console.log(onlyEven); //  4
  *    */
 
-const evenOccurence = (arr) => {
-  // Your code here.
-};
+function evenOccurrence (arr) {
+  var storage = {};
+
+  arr.forEach((item) => {
+    storage[item] = storage[item] + 1 || 1;
+  });
+
+  for (var i = 0; i < arr.length; i++) {
+    if (storage[arr[i]] % 2 === 0) {
+      return current;
+    }
+  }
+  return null;
+}
+
+console.log(evenOccurrence([1, 7, 2, 4, 5, 1, 6, 8, 9, 6, 4, 1]));
\ No newline at end of file
diff --git a/forLoopTimeout/forLoopTimeout.js b/forLoopTimeout/forLoopTimeout.js
index 87522c2..e9e6051 100644
--- a/forLoopTimeout/forLoopTimeout.js
+++ b/forLoopTimeout/forLoopTimeout.js
@@ -10,4 +10,12 @@ for (var i = 1; i <= 10; i++) {
 		// It doesn't.  Why?  How can you make it print 1 - 10.
 		console.log(i);
 	}, 0);
+}
+
+// Closure issue. Var is globally scoped, change to let. 
+
+for (let i = 1; i <= 10; i++) {
+	setTimeout(function() {
+		console.log(i);
+	}, 0);
 }
\ No newline at end of file
diff --git a/isUnique/isUnique.js b/isUnique/isUnique.js
index 6c9caf5..196d053 100644
--- a/isUnique/isUnique.js
+++ b/isUnique/isUnique.js
@@ -1,3 +1,13 @@
 /* Implement an algorithm to determine if a string has all unique characters.
  * What if you cannot use additional data structures?
- */
\ No newline at end of file
+ */
+ const isUnique = (str) => {
+ 	const uniqueStr = new Set();
+ 	for (let i = 0; i < str.length; i++) {
+ 		if (uniqueStr.has(str[i])) {
+ 			return false;
+ 		}
+ 		uniqueStr.add(str[i]);
+ 	}
+ 	return true;
+ }
\ No newline at end of file
diff --git a/largestPrimePalindrome/largestPrimePalindrome.js b/largestPrimePalindrome/largestPrimePalindrome.js
index 4cc99c0..b1f267d 100644
--- a/largestPrimePalindrome/largestPrimePalindrome.js
+++ b/largestPrimePalindrome/largestPrimePalindrome.js
@@ -3,4 +3,23 @@
  * Hint: it's 929
  * You will first want to determine if the number is a palindrome and then determine if it is prime.
  * A palindrome is a number that is the same forwards and backwards: 121, 323, 123454321, etc.
- */
\ No newline at end of file
+ */
+
+const largestPrimePalindrome = () => {
+	const isPalindrome = (num) => {
+		if (num === num.toString().split('').reverse().join('')) return true;
+	} 
+
+	const isPrime = (num) => {
+		if (num % 2 !== 0) {
+			for (let j = 3; j <= Math.sqrt(num); j++) {
+				if (num % j === 0) return false;
+			}
+			return true;
+		}
+	}
+	
+	for (let i = 1000; i > 0; i--) {
+		if (isPalindrome(i) && isPrime(i)) return i;
+	 }
+  }
\ No newline at end of file
diff --git a/longestString/longestString.js b/longestString/longestString.js
index 35b887c..130a72e 100644
--- a/longestString/longestString.js
+++ b/longestString/longestString.js
@@ -2,3 +2,12 @@
  * Write a function that accepts an array of strings.
  * Return the longest string in the array.
  */
+const longestString = (arr) => {
+	let longest = arr[0];
+	for (let i = 0; i < arr.length; i++) {
+		if (arr[i].length > longest.length) {
+			longest = arr[i];
+		}
+	}
+	return longest;
+};
\ No newline at end of file
diff --git a/removeDuplicates/removeDuplicates.js b/removeDuplicates/removeDuplicates.js
index 970f719..edd7858 100644
--- a/removeDuplicates/removeDuplicates.js
+++ b/removeDuplicates/removeDuplicates.js
@@ -8,6 +8,26 @@
  *  you're more than likely using a for loop under the hood.
  */
 
+//initial code
 const removeDuplicates = (arr) => {
-	//code here...
-};
\ No newline at end of file
+	const newArr = [];
+	for (let i = 0; i < arr.length; i++) {
+		if(!(newArr.includes(arr[i]))) {
+			newArr.push(arr[i]);
+		}
+	}
+	return newArr;
+};
+
+//"beast mode"
+const removeDuplicates = (arr) => {
+	const newArr = [];
+	const obj = {};
+	for (let i =0; i < arr.length; i++) {
+		if (!obj[arr[i]]) {
+			obj[arr[i]] = true;
+			newArr.push(arr[i]);
+		}
+	}
+	return newArr;
+}
\ No newline at end of file
diff --git a/reverseCase/reverseCase.js b/reverseCase/reverseCase.js
index f1051f5..943e0c8 100644
--- a/reverseCase/reverseCase.js
+++ b/reverseCase/reverseCase.js
@@ -2,4 +2,16 @@
  * Write a function that reverses the case of each letter in the strings that it receives.
  * Example: 'Hello World' -> 'hELLO wORLD'
  * Assume that each string will contain only spaces and letters.
- */
\ No newline at end of file
+ */
+
+ const reverseCase = (string) => {
+ 	let newStr = '';
+ 	for (let i = 0; i < string.length; i++) {
+ 		if (string[i] === string[i].toUpperCase()) {
+ 			newStr = newStr.concat(string[i].toLowerCase());
+ 		} else {
+ 			newStr = newStr.concat(string[i].toUpperCase());
+ 		}
+ 	}
+ 	return newStr;
+ }
\ No newline at end of file
diff --git a/stringCompression/stringCompression.js b/stringCompression/stringCompression.js
index 48db571..dd3eeef 100644
--- a/stringCompression/stringCompression.js
+++ b/stringCompression/stringCompression.js
@@ -4,3 +4,19 @@
 // If the "compressed" string would not become smaller than the original string,
 // your method should return the original string.
 // You can assume the string has only uppercase and lowercase letters (a - z).
+
+const compressString = (string) => {
+  let currentChar = string.charAt(0);
+  let compressedString = '';
+  let charCount = 0;
+  for (let i = 0; i < string.length; i++) {
+    if (string.charAt(i) === currentChar) charCount++;
+    if (string.charAt(i) !== currentChar || string.charAt(i) === undefined) {
+      compressedString += currentChar;
+      compressedString += charCount;
+      charCount = 1;
+      currentChar = string.charAt(i);
+    }
+  }
+  return compressedString.length > string.length ? string : compressedString;
+}
\ No newline at end of file
diff --git a/vowelCount/vowelCount.js b/vowelCount/vowelCount.js
index 27fad79..61d55dc 100644
--- a/vowelCount/vowelCount.js
+++ b/vowelCount/vowelCount.js
@@ -2,3 +2,15 @@
  * Write a function that returns the count of the total number of vowels in a string.
  * Example: 'Hello World!' -> 3
  */
+
+ const vowelCount = (str) => {
+  const vowels = ['a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U']; 
+  let count = 0;
+
+  for (let i = 0; i < str.length; i++) {
+    if (vowels.indexOf(str[i]) > -1) {
+      counter++;
+    }
+  }
+  return counter;
+ };
\ No newline at end of file