diff --git a/1-exercises/A-undefined/exercise.js b/1-exercises/A-undefined/exercise.js
index 0acfc78d..8d2195bf 100644
--- a/1-exercises/A-undefined/exercise.js
+++ b/1-exercises/A-undefined/exercise.js
@@ -12,6 +12,7 @@
 // Example 1
 let a;
 console.log(a);
+//a isn't given a value. 
 
 
 // Example 2
@@ -21,6 +22,7 @@ function sayHello() {
 
 let hello = sayHello();
 console.log(hello);
+//the function doesn't return anything.
 
 
 // Example 3
@@ -29,8 +31,10 @@ function sayHelloToUser(user) {
 }
 
 sayHelloToUser();
+//Nothing has been written inside the parantheses when calling the function.
 
 
 // Example 4
 let arr = [1,2,3];
 console.log(arr[3]);
+//the array holds values from 0-2, so 3 doesn't exist.
diff --git a/1-exercises/B-array-literals/exercise.js b/1-exercises/B-array-literals/exercise.js
index 51eba5cc..5bec732c 100644
--- a/1-exercises/B-array-literals/exercise.js
+++ b/1-exercises/B-array-literals/exercise.js
@@ -4,8 +4,8 @@
   Declare some variables assigned to arrays of values
 */
 
-let numbers = []; // add numbers from 1 to 10 into this array
-let mentors; // Create an array with the names of the mentors: Daniel, Irina and Rares
+let numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]; // add numbers from 1 to 10 into this array
+let mentors = ["Daniel", "Irina", "Rares"]; // Create an array with the names of the mentors: Daniel, Irina and Rares
 
 /* 
   DO NOT EDIT BELOW THIS LINE
diff --git a/1-exercises/C-array-get-set/exercise.js b/1-exercises/C-array-get-set/exercise.js
index 5ca911d5..9c1d01d7 100644
--- a/1-exercises/C-array-get-set/exercise.js
+++ b/1-exercises/C-array-get-set/exercise.js
@@ -5,11 +5,11 @@
 */
 
 function first(arr) {
-  return; // complete this statement
+  return arr[0]; // complete this statement
 }
 
 function last(arr) {
-  return; // complete this statement
+  return arr[arr.length - 1]; // complete this statement
 }
 
 /* 
diff --git a/1-exercises/C-array-get-set/exercises2.js b/1-exercises/C-array-get-set/exercises2.js
index 6b6b007a..fdd67033 100644
--- a/1-exercises/C-array-get-set/exercises2.js
+++ b/1-exercises/C-array-get-set/exercises2.js
@@ -6,8 +6,9 @@
   - change the first value in the array to the number 1
 */
 
-let numbers = [1, 2, 3]; // Don't change this array literal declaration
-
+let numbers = [1, 2, 3]; 
+numbers.push(4);// Don't change this array literal declaration
+numbers[0] = 1;
 /* 
   DO NOT EDIT BELOW THIS LINE
   --------------------------- */
diff --git a/1-exercises/D-for-loop/exercise.js b/1-exercises/D-for-loop/exercise.js
index 081002b2..789e3665 100644
--- a/1-exercises/D-for-loop/exercise.js
+++ b/1-exercises/D-for-loop/exercise.js
@@ -10,21 +10,9 @@
     Using a for loop, output to the console a line about the age of each writer.
 */
 
-const WRITERS = [
-    "Virginia Woolf",
-    "Zadie Smith",
-    "Jane Austen",
-    "Bell Hooks",
-    "Yukiko Motoya"
-]
-
-const AGES = [
-    59,
-    40,
-    41,
-    63,
-    49
-];
+const WRITERS = ["Virginia Woolf", "Zadie Smith", "Jane Austen", "Bell Hooks", "Yukiko Motoya"]
+const AGES = [59, 40, 41, 63, 49];
+for (i = 0, i <  )
 
 // TODO - Write for loop code here
 
diff --git a/1-exercises/E-while-loop-with-array/exercise.js b/1-exercises/E-while-loop-with-array/exercise.js
index d584cd75..e191cd84 100644
--- a/1-exercises/E-while-loop-with-array/exercise.js
+++ b/1-exercises/E-while-loop-with-array/exercise.js
@@ -17,7 +17,10 @@ const BIRTHDAYS = [
 ];
 
 function findFirstJulyBDay(birthdays) {
-    // TODO
+    while(i <= BIRTHDAYS.length) { 
+            if (array[i] === July) {
+                return i;
+            }
 }
 
-console.log(findFirstJulyBDay(BIRTHDAYS)); // should output "July 11th"
+console.log(findFirstJulyBDay(BIRTHDAYS)); }
\ No newline at end of file
diff --git a/2-mandatory/1-weather-report.js b/2-mandatory/1-weather-report.js
index dcc2bdb0..9706d1e2 100644
--- a/2-mandatory/1-weather-report.js
+++ b/2-mandatory/1-weather-report.js
@@ -12,7 +12,14 @@
 */
 
 function getTemperatureReport(cities) {
-    // TODO
+  const temperatureReport = [];
+  
+  for (let i = 0; i < cities.length; i++) {
+    const temperature = temperatureService(cities[i]);
+    temperatureReport.push(`The temperature in ${cities[i]} is ${temperature} degrees`);
+  }
+  
+  return temperatureReport;
 }
 
 
diff --git a/2-mandatory/2-financial-times.js b/2-mandatory/2-financial-times.js
index 2ce6fb73..240dd92c 100644
--- a/2-mandatory/2-financial-times.js
+++ b/2-mandatory/2-financial-times.js
@@ -5,16 +5,33 @@
     Implement the function below, which will return a new array containing only article titles which will fit.
 */
 function potentialHeadlines(allArticleTitles) {
-    // TODO
-}
+  const potentialHeadlines = [];
+
+  for (let i = 0; i < allArticleTitles.length; i++) {
+    const articleTitle = allArticleTitles[i];
+
+    if (articleTitle.length <= 65) {
+      potentialHeadlines.push(articleTitle);
+    }
+  }
 
+  return potentialHeadlines;
+}
+   
 /*
     The editor of the FT likes short headlines with only a few words!
     Implement the function below, which returns the title with the fewest words.
     (you can assume words will always be seperated by a space)
 */
 function titleWithFewestWords(allArticleTitles) {
-    // TODO
+    let shortestTitle = allArticleTitles[0];
+
+    for (let i=1; i<allArticleTitles.length; i++) {
+        if (allArticleTitles[i].length < shortestTitle.length) {
+            shortestTitle = allArticleTitles[i];
+        }
+    }
+    return shortestTitle;
 }
 
 /*
@@ -23,19 +40,33 @@ function titleWithFewestWords(allArticleTitles) {
     (Hint: remember that you can also loop through the characters of a string if you need to)
 */
 function headlinesWithNumbers(allArticleTitles) {
-    // TODO
-}
+  const result = [];
+  for (let i = 0; i < allArticleTitles.length; i++) {
+    if (/[\d]/.test(allArticleTitles[i]))
+    result.push(allArticleTitles[i]);
+    }
+    return result; 
+  }
+  
+
 
 /*
     The Financial Times wants to understand what the average number of characters in an article title is.
     Implement the function below to return this number - rounded to the nearest integer.
 */
 function averageNumberOfCharacters(allArticleTitles) {
-    // TODO
+  let totalChars = 0;
+  for (let i = 0; i < allArticleTitles.length; i++) {
+    totalChars += allArticleTitles[i].length;
+  }
+  const averageChars = totalChars / allArticleTitles.length;
+  return Math.round(averageChars);
 }
 
 
 
+
+
 /* ======= List of Articles - DO NOT MODIFY ===== */
 const ARTICLE_TITLES = [
     "Streaming wars drive media groups to spend more than $100bn on new content",
diff --git a/2-mandatory/3-stocks.js b/2-mandatory/3-stocks.js
index 72d62f94..c0d51420 100644
--- a/2-mandatory/3-stocks.js
+++ b/2-mandatory/3-stocks.js
@@ -7,6 +7,7 @@
             For example, CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS[2] contains the prices for the last 5 days for STOCKS[2] (which is amzn)
 */
 
+
 /* ======= Stock data - DO NOT MODIFY ===== */
 const STOCKS = ["aapl", "msft", "amzn", "googl", "tsla"];
 
@@ -34,9 +35,26 @@ const CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS = [
         Functions can help with this!
 */
 function getAveragePrices(closingPricesForAllStocks) {
-    // TODO
-}
+  // Create an empty array to hold the average prices for each stock
+  const averagePrices = [];
+
+  // Loop through each array of closing prices for each stock
+  for (let i = 0; i < closingPricesForAllStocks.length; i++) {
+    // Get the array of closing prices for the current stock
+    const stockPrices = closingPricesForAllStocks[i];
+    
+    // Calculate the sum of all closing prices for the current stock
+    const sum = stockPrices.reduce((acc, cur) => acc + cur);
+
+    // Calculate the average closing price for the current stock
+    const avg = sum / stockPrices.length;
+
+    // Round the average closing price to 2 decimal places and add it to the array
+    averagePrices.push(parseFloat(avg.toFixed(2)));
+  }
 
+  return averagePrices;
+}
 /*
     We also want to see what the change in price is from the first day to the last day for each stock.
     Implement the below function, which
@@ -48,7 +66,15 @@ function getAveragePrices(closingPricesForAllStocks) {
     The price change value should be rounded to 2 decimal places, and should be a number (not a string)
 */
 function getPriceChanges(closingPricesForAllStocks) {
-    // TODO
+  const priceChanges = [];
+  
+  for (let i = 0; i < closingPricesForAllStocks.length; i++) {
+    const prices = closingPricesForAllStocks[i];
+    const priceChange = (prices[prices.length-1] - prices[0]).toFixed(2);
+    priceChanges.push(parseFloat(priceChange));
+  }
+  
+  return priceChanges;
 }
 
 /*
@@ -64,7 +90,16 @@ function getPriceChanges(closingPricesForAllStocks) {
     The price should be shown with exactly 2 decimal places.
 */
 function highestPriceDescriptions(closingPricesForAllStocks, stocks) {
-    // TODO
+    const priceDescriptions = [];
+
+    for (let i = 0; i < stocks.length; i++) {
+        const ticker = stocks[i].toUpperCase();
+        const highestPrice = Math.max(...closingPricesForAllStocks[i]).toFixed(2);
+        priceDescriptions.push(`The highest price of ${ticker} in the last 5 days was ${highestPrice}`);
+
+    }
+
+    return priceDescriptions;
 }
 
 
diff --git a/3-extra/1-radio-stations.js b/3-extra/1-radio-stations.js
index 577076e9..db031027 100644
--- a/3-extra/1-radio-stations.js
+++ b/3-extra/1-radio-stations.js
@@ -31,28 +31,20 @@
  * Note: You are not expected to understand everything below this comment!
  */
 
-function getAvailableStations() {
-  // Using `stations` as a property as defining it as a global variable wouldn't
-  // always make it initialized before the function is called
-  if (!getAvailableStations.stations) {
-    const stationCount = 4;
-    getAvailableStations.stations = [];
-    while (getAvailableStations.stations.length < stationCount) {
-      let randomFrequency = Math.floor(Math.random() * (108 - 87 + 1) + 87);
-      if (!getAvailableStations.stations.includes(randomFrequency)) {
-        getAvailableStations.stations.push(randomFrequency);
-      }
-    }
-    getAvailableStations.stations.sort(function (frequencyA, frequencyB) {
-      return frequencyA - frequencyB;
-    });
+function getAllFrequencies() {
+  const frequencies = [];
+  for (let i = 87; i <= 108; i++) {
+    frequencies.push(i);
   }
-
-  return getAvailableStations.stations;
+  return frequencies;
 }
 
-function isRadioStation(frequency) {
-  return getAvailableStations().includes(frequency);
+function getStations() {
+  const allFrequencies = getAllFrequencies();
+  const radioStations = allFrequencies.filter((frequency) => {
+    return isRadioStation(frequency);
+  });
+  return radioStations;
 }
 
 test("getAllFrequencies() returns all frequencies between 87 and 108", () => {
diff --git a/3-extra/2-array-of-objects.js b/3-extra/2-array-of-objects.js
index ee57960f..fe56f13c 100644
--- a/3-extra/2-array-of-objects.js
+++ b/3-extra/2-array-of-objects.js
@@ -11,9 +11,21 @@
 */
 
 function getHighestRatedInEachGenre(books) {
-    // TODO
-}
+  // this object will store the highest rated books for each genre
+  const highestRated = {};
+
+  // I'll loop through the books array and update the highest rated book for each genre
+  books.forEach(book => {
+    if (!highestRated[book.genre] || book.rating > highestRated[book.genre].rating) {
+      highestRated[book.genre] = book;
+    }
+  });
 
+  // this will return an array of book titles from the highest rated books object
+  const titles = Object.values(highestRated).map(book => book.title);
+
+  return titles;
+}
 
 /* ======= Book data - DO NOT MODIFY ===== */
 const BOOKS = [
diff --git a/3-extra/3-fibonacci.js b/3-extra/3-fibonacci.js
index 9ef9aec7..c64aa38d 100644
--- a/3-extra/3-fibonacci.js
+++ b/3-extra/3-fibonacci.js
@@ -14,7 +14,13 @@
 */
 
 function generateFibonacciSequence(n) {
-    // TODO
+  let fibonacciSequence = [0, 1];
+
+  for (let i = 2; i < n; i++) {
+    fibonacciSequence[i] = fibonacciSequence[i - 1] + fibonacciSequence[i - 2];
+  }
+
+  return fibonacciSequence;
 }
 
 /* ======= TESTS - DO NOT MODIFY ===== */