diff --git a/1-exercises/A-undefined/exercise.js b/1-exercises/A-undefined/exercise.js
index 0acfc78d..076fc9f6 100644
--- a/1-exercises/A-undefined/exercise.js
+++ b/1-exercises/A-undefined/exercise.js
@@ -11,12 +11,12 @@
 
 // Example 1
 let a;
-console.log(a);
+console.log(a);  //it will be undefined because it does not have any value
 
 
 // Example 2
 function sayHello() {
-    let message = "Hello";
+    let message = "Hello"; //hello is not a string in console.log, so the program reads it as variable, but "hello" doesn't exist.
 }
 
 let hello = sayHello();
@@ -28,9 +28,10 @@ function sayHelloToUser(user) {
     console.log(`Hello ${user}`);
 }
 
-sayHelloToUser();
+sayHelloToUser();  //when calling function we don't pass any value for parameter user
+
 
 
 // Example 4
 let arr = [1,2,3];
-console.log(arr[3]);
+console.log(arr[3]); //element in arr with index 3 doesn't exist. There only 0, 1, 2.
diff --git a/1-exercises/B-array-literals/exercise.js b/1-exercises/B-array-literals/exercise.js
index 51eba5cc..e0034349 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", "Irina"]// 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..672aa87e 100644
--- a/1-exercises/C-array-get-set/exercise.js
+++ b/1-exercises/C-array-get-set/exercise.js
@@ -4,12 +4,12 @@
   Complete the functions below to get the first and last values from the array
 */
 
-function first(arr) {
-  return; // complete this statement
+function first( numbers) {
+  return [0] [2]; // complete this statement
 }
 
-function last(arr) {
-  return; // complete this statement
+function last(names) {
+  return[3]; // 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..caf5aaff 100644
--- a/1-exercises/C-array-get-set/exercises2.js
+++ b/1-exercises/C-array-get-set/exercises2.js
@@ -6,8 +6,8 @@
   - 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 = [2, 3, 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..7c31cd44 100644
--- a/1-exercises/D-for-loop/exercise.js
+++ b/1-exercises/D-for-loop/exercise.js
@@ -37,3 +37,8 @@ Jane Austen is 41 years old
 Bell Hooks is 63 years old
 Yukiko Motoya is 49 years old
 */
+const AGES = [59, 40, 41, 63, 49];
+
+for (let i = 0; i < WRITERS.length; i++) {
+  console.log(WRITERS[i] + " is " + AGES[i] + " years old");
+}
\ No newline at end of file
diff --git a/1-exercises/E-while-loop-with-array/exercise.js b/1-exercises/E-while-loop-with-array/exercise.js
index d584cd75..97a31ee7 100644
--- a/1-exercises/E-while-loop-with-array/exercise.js
+++ b/1-exercises/E-while-loop-with-array/exercise.js
@@ -15,9 +15,19 @@ const BIRTHDAYS = [
     "September 28th",
     "November 15th"
 ];
+//let count = 0;
 
-function findFirstJulyBDay(birthdays) {
+function findFirstJulyBDay(parameter) {
     // TODO
-}
+   //let i = 0;
+   let currentIndex = 0;
+    while(currentIndex < parameter.length){
+        if(parameter[currentIndex].includes('July')){
+            return parameter[currentIndex];
+        }
+        console.log(parameter[currentIndex])
+        currentIndex++;
+    }
 
-console.log(findFirstJulyBDay(BIRTHDAYS)); // should output "July 11th"
+ // should output "July 11th"
+}
diff --git a/2-mandatory/1-weather-report.js b/2-mandatory/1-weather-report.js
index dcc2bdb0..4d13ce82 100644
--- a/2-mandatory/1-weather-report.js
+++ b/2-mandatory/1-weather-report.js
@@ -13,9 +13,25 @@
 
 function getTemperatureReport(cities) {
     // TODO
-}
-
+    let arr = [];
+  let degree = 0;
+  let cityDegree = "";
+  for (let i = 0; i < cities.length; i++) {
+    degree = temperatureService(cities[i]);
+    
+    arr.push(cityDegree);
+  }
+  return arr;
 
+} let arr = [];
+  let degree = 0;
+  let cityDegree = "";
+  for (let i = 0; i < cities.length; i++) {
+    degree = temperatureService(cities[i]);
+    cityDegree = `The temperature in ${cities[i]} is ${degree} degrees`;
+     arr.push(cityDegree);
+  }
+ return arr
 /* ======= TESTS - DO NOT MODIFY ===== */
 
 function temperatureService(city) {
diff --git a/2-mandatory/2-financial-times.js b/2-mandatory/2-financial-times.js
index 2ce6fb73..8e972be7 100644
--- a/2-mandatory/2-financial-times.js
+++ b/2-mandatory/2-financial-times.js
@@ -6,6 +6,17 @@
 */
 function potentialHeadlines(allArticleTitles) {
     // TODO
+    function potentialHeadlines(allArticleTitles) {
+    // TODO
+  let shortArticles = [];
+  for (let article of allArticleTitles) {
+    if (article.length <= 65) {
+      shortArticles.push(article);
+    }
+  }
+  return shortArticles;
+}
+    
 }
 
 /*
@@ -15,6 +26,14 @@ function potentialHeadlines(allArticleTitles) {
 */
 function titleWithFewestWords(allArticleTitles) {
     // TODO
+      const myArray = [];
+  for (let article of allArticleTitles) {
+    myArray.push(article.split(" "));
+  } 
+  let result = myArray.reduce(function (a,b) {
+    return a.length <= b.length ? a : b; 
+  });
+  return allArticleTitles[myArray.indexOf(result)]; 
 }
 
 /*
@@ -24,18 +43,40 @@ function titleWithFewestWords(allArticleTitles) {
 */
 function headlinesWithNumbers(allArticleTitles) {
     // TODO
+    let countArray = [];
+  for (article of allArticleTitles) {
+    countArray.push(article.length);
+  }
+  let sum = 0;
+  for (let i = 0; i < countArray.length; i++) {
+    sum += countArray[i];
+  }
+  return Math.round(sum / countArray.length);
 }
 
+
+
+
 /*
     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 countArray = [];
+  for (article of allArticleTitles) {
+    countArray.push(article.length);
+  }
+  let sum = 0;
+  for (let i = 0; i < countArray.length; i++) {
+    sum += countArray[i];
+  }
+  return Math.round(sum / countArray.length);
 }
 
 
 
+
 /* ======= 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..d0e61cf7 100644
--- a/2-mandatory/3-stocks.js
+++ b/2-mandatory/3-stocks.js
@@ -35,8 +35,16 @@ const CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS = [
 */
 function getAveragePrices(closingPricesForAllStocks) {
     // TODO
+    let averageOfWeek = [];
+  //looping through array of arrays and calling findAveragePrice method on each array
+  for (let averageOfWeek of closingPricesForAllStocks) {
+    averageOfWeek.push(findAveragePrice(averageOfWeek));
+  }
+  return averageOfWeek;
 }
 
+
+
 /*
     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
@@ -49,6 +57,13 @@ function getAveragePrices(closingPricesForAllStocks) {
 */
 function getPriceChanges(closingPricesForAllStocks) {
     // TODO
+    let result =[];
+
+    for( let i = 0; i< closingPricesForAllStocks.length; i++) {
+        let diff =0;
+        diff = closingPricesForAllStocks[i][4] - closingPricesForAllStocks[i][0];
+        result.push(parseFloat(diff.toFixed(2)));
+    }
 }
 
 /*
@@ -65,6 +80,19 @@ function getPriceChanges(closingPricesForAllStocks) {
 */
 function highestPriceDescriptions(closingPricesForAllStocks, stocks) {
     // TODO
+
+    let arr = [];
+    for (let i = 0; i < closingPricesForAllStocks.length; i++) {
+      arr.push(
+        `The highest price of ${stocks[
+          i
+        ].toUpperCase()} in the last 5 days was ${Math.max(
+          ...closingPricesForAllStocks[i]
+        ).toFixed(2)}`
+      );
+    }
+    return arr;
+
 }