diff --git a/.vscode/settings.json b/.vscode/settings.json
index 8eb2651..69066d1 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -3,5 +3,6 @@
   "[javascript]": {
     "editor.defaultFormatter": "esbenp.prettier-vscode"
   },
-  "editor.formatOnSave": true
+  "editor.formatOnSave": true,
+  "terminal.integrated.sendKeybindingsToShell": true
 }
diff --git a/src/00-hello-world.ts b/src/00-hello-world.ts
index b516ceb..cdbaa7d 100644
--- a/src/00-hello-world.ts
+++ b/src/00-hello-world.ts
@@ -12,7 +12,7 @@ export {};
  */
 
 const helloWorld = function() {
-  return "";
+  return "Hello World";
 };
 
-console.log(); // Expected output: "Hello World"
+console.log(helloWorld()); // Expected output: "Hello World"
diff --git a/src/01-syntax-error.ts b/src/01-syntax-error.ts
index bb34c60..08b7d3b 100644
--- a/src/01-syntax-error.ts
+++ b/src/01-syntax-error.ts
@@ -1,8 +1,13 @@
 export {};
 
-function addNumbers(a b c) {
+function addNumbers(a: number, b: number, c: number) {
     return a + b + c;
 }
 
 const result = addNumbers(1, 3, 4);
+const result1 = addNumbers(2, 3, 5);
+const result2 = addNumbers(1, 3, 888);
+
 console.log(result); // Expected output: 8
+console.log(result1);
+console.log(result2);
diff --git a/src/02-syntax-error.ts b/src/02-syntax-error.ts
index e18d89c..658f029 100644
--- a/src/02-syntax-error.ts
+++ b/src/02-syntax-error.ts
@@ -1,7 +1,7 @@
 export {};
 
-function addNumbers(a, b, c)
-    a + b + c;
-
+function addNumbers(a:number, b: number, c: number){
+   return a + b + c;
+}
 const result = addNumbers(1, 3, 4);
 console.log(result); // Expected output: 8
diff --git a/src/03-syntax-error.ts b/src/03-syntax-error.ts
index f7f565e..373e3ce 100644
--- a/src/03-syntax-error.ts
+++ b/src/03-syntax-error.ts
@@ -1,6 +1,6 @@
 export {};
 
-function(a, b, c) {
+function addNumbers (a:number, b: number, c: number) {
     return a + b + c;
 }
 
diff --git a/src/04-logic-error.ts b/src/04-logic-error.ts
index 29a4b64..3bddcd7 100644
--- a/src/04-logic-error.ts
+++ b/src/04-logic-error.ts
@@ -1,7 +1,7 @@
 export {};
 
-function trimWord(word) {
-  return wordtrim();
+function trimWord(word: string):string {
+  return word.trim();
 }
 
 const result = trimWord("  CODELEX ");
diff --git a/src/05-boolean.ts b/src/05-boolean.ts
index c597246..26dc676 100644
--- a/src/05-boolean.ts
+++ b/src/05-boolean.ts
@@ -1,11 +1,15 @@
 export {};
 
-const isHappy = "true";
+const isHappy = true;
 
-if (isHappy == false) {
+if (isHappy) {
   console.log("I am happy");
 } else {
   console.log("I am not happy");
 }
 
-// Expected output: "I am happy"
+// Expected output: "I am happy 
+
+//2. isHappy ? console.log("I am happy") : console.log("I am not happy");
+
+//3. console.log(`I am ${isHappy ? '' : 'not' }happy`)
diff --git a/src/06-logic-error.ts b/src/06-logic-error.ts
index 69a4840..d0dc789 100644
--- a/src/06-logic-error.ts
+++ b/src/06-logic-error.ts
@@ -1,7 +1,7 @@
 export {};
 
-function trimWord(word) {
-  return word.trim;
+function trimWord(word: string): string{
+  return word.trim();
 }
 
 const result = trimWord("  CODELEX ");
diff --git a/src/07-logic-error.ts b/src/07-logic-error.ts
index 30f8ccf..a21bd36 100644
--- a/src/07-logic-error.ts
+++ b/src/07-logic-error.ts
@@ -1,7 +1,7 @@
 export {};
 
-function trim(word) {
-  return "word".trim();
+function trim(word: string): string {
+  return word.trim();
 }
 
 const result = trim("CODELEX  ");
diff --git a/src/08-function-output.ts b/src/08-function-output.ts
index ffe1717..f20ee0c 100644
--- a/src/08-function-output.ts
+++ b/src/08-function-output.ts
@@ -1,8 +1,8 @@
 export {};
 
-function getNumber() {
-  return Math.random() * 10;
+function getRandomNumber() {
+  return Math.round(Math.random() * 10);
 }
 
-const result = null; // call the function created above and put the result inside the variable
+const result = getRandomNumber(); // call the function created above and put the result inside the variable
 console.log(result); // Expected output: {random number}
diff --git a/src/09-logic-error.ts b/src/09-logic-error.ts
index fdb0169..99d6c58 100644
--- a/src/09-logic-error.ts
+++ b/src/09-logic-error.ts
@@ -1,8 +1,8 @@
 export {};
 
-function multiply(a, b, c) {
-  a * b * c;
-  return;
+function multiply(a: number, b: number, c: number): number {
+  return a * b * c;
+  
 }
 
 const result = multiply(1, 3, 4);
diff --git a/src/10-function-output.ts b/src/10-function-output.ts
index d65dc24..8afb1c1 100644
--- a/src/10-function-output.ts
+++ b/src/10-function-output.ts
@@ -1,8 +1,9 @@
 export {};
 
-function s(w1, w2) {
-  return w1.concat(' ').concat(w2);
+function joinString(w1: string, w2: string): string {
+  //return w1.concat(' '). concat(w2);
+  return w1.concat(" ", w2);
 }
 
-const result = undefined; // concatenate two strings - 'hello', 'world', using the function above
+const result = joinString ('hello','world'); // concatenate two strings - 'hello', 'world', using the function above
 console.log(result); // Expected output: "hello world"
diff --git a/src/11-function-output.ts b/src/11-function-output.ts
index 3c783dd..159ac0e 100644
--- a/src/11-function-output.ts
+++ b/src/11-function-output.ts
@@ -1,6 +1,12 @@
 export {};
 
-function concatenate(firstWord, secondWord, thirdWord) {
+function concatenate(
+  firstWord: string, 
+  secondWord: string, 
+  thirdWord: string):
+  string {
+    
+  return `${firstWord} ${secondWord} ${thirdWord}`;
   // Write the body of this function to concatenate three words together with space between them
 }
 
diff --git a/src/12-truncate-string.ts b/src/12-truncate-string.ts
index 1ada061..3bf5723 100644
--- a/src/12-truncate-string.ts
+++ b/src/12-truncate-string.ts
@@ -1,3 +1,31 @@
 export {};
 
-console.log(truncateString("CODELEX", 4)); // Expected output: CODE
+function truncateString(str: string, length: number):string{
+    //return str.substring(0,length)
+
+
+   // Expected output: CODE
+
+  
+   let result = "";
+    
+  for(let i = 0; i < length; i++){
+      console.log('i, str[i]:', i, str[i]);
+
+      result = result + str[i];
+      console.log('result: ', result);
+      console.log('=======================');
+    }
+    return result;
+
+  }
+      console.log (truncateString ("CODELEX", 4));
+  
+    
+  
+        
+
+
+
+
+  
\ No newline at end of file
diff --git a/src/13-is-blank.ts b/src/13-is-blank.ts
index 92d00d2..d493b29 100644
--- a/src/13-is-blank.ts
+++ b/src/13-is-blank.ts
@@ -1,8 +1,18 @@
 export {};
 
-/**
- * Create a function called isBlank, which checks if passed string is blank or not
- */
+
+ // Create a function called isBlank, which checks if passed string is blank or not
+ 
+
+  function isBlank(value: string | null): boolean {
+   if(value === null) {
+        return true;
+    }
+    if (value.trim() === ""){
+        return true;
+    }
+    return false;
+}
 
 console.log(isBlank(null)); // Expected output: true
 console.log(isBlank("")); // Expected output: true
diff --git a/src/14-repeat-string.ts b/src/14-repeat-string.ts
index 9bb46e7..5c7fd0d 100644
--- a/src/14-repeat-string.ts
+++ b/src/14-repeat-string.ts
@@ -1,6 +1,13 @@
 export {};
 
-const repeatString = () => {};
+const repeatString = (str: string, timesToRepeat: number): string => {
+ // return str.repeat(timesToRepeat);
+    let result = str;
+    for(let i = 1; i < timesToRepeat; i++){
+        result += str;   //result = result + str;
+    }
+    return result; 
+};
 
 console.log(repeatString("a", 4)); // Expected output: 'aaaa'
-console.log(repeatString("b", 5)); // Expected output: 'bbbbb'
+console.log(repeatString("bob", 5)); // Expected output: 'bbbbb'
diff --git a/src/15-greatest-number.ts b/src/15-greatest-number.ts
index 68cedbb..1801ec7 100644
--- a/src/15-greatest-number.ts
+++ b/src/15-greatest-number.ts
@@ -1,6 +1,8 @@
 export {};
 
-function greatest(x, y) {}
+function greatest(x: number, y: number) {
+    
+}
 
 console.log(greatest(1, 2)); // Expected output: 2
 console.log(greatest(5, 2)); // Expected output: 5
diff --git a/src/16-tax.ts b/src/16-tax.ts
index 0938535..dd62ce4 100644
--- a/src/16-tax.ts
+++ b/src/16-tax.ts
@@ -13,7 +13,9 @@ export {};
  */
 
 // You are allowed to change only this function
-function calculateSalesTax() {}
+function calculateSalesTax(price: number): string {
+    return (price * 0.21).toFixed(2);
+}
 
 const product = "You don't know JS";
 const price = 19.99;
diff --git a/src/17-format-currency.ts b/src/17-format-currency.ts
index e172c35..082792f 100644
--- a/src/17-format-currency.ts
+++ b/src/17-format-currency.ts
@@ -9,8 +9,11 @@ export {};
  */
 
 // You are allowed to change only this function
-function formatCurrency() {}
 
+function formatCurrency(num: number): string{
+  return num.toFixed(2)
+}
+ 
 function calculateSalesTax(price: number) {
   return price * 0.21;
 }
diff --git a/src/18-currency-conversion.ts b/src/18-currency-conversion.ts
index 0b789ab..ad597a2 100644
--- a/src/18-currency-conversion.ts
+++ b/src/18-currency-conversion.ts
@@ -8,11 +8,20 @@ export {};
  */
 
 // You are allowed to change only this function
-function convertToUSD() {}
+/*
+const CONVERSION_RATE_EUR_USD = 1.09;
+
+function convertToUSD() {
+
+    }
+    function addFee(price: number): number{
+        return price + price * CONVERSION_FEE;
+    }
+
 
 const product = "You don't know JS";
 const price = 19.99;
-const priceInUSD = convertToUSD(price);
+const priceInUSD = convertToUSD(price );
 
 console.log("Product: " + product);
 console.log("Price: $" + priceInUSD);
diff --git a/src/19-currency-conversion.ts b/src/19-currency-conversion.ts
index 1d057d9..93aee62 100644
--- a/src/19-currency-conversion.ts
+++ b/src/19-currency-conversion.ts
@@ -15,14 +15,29 @@ export {};
  */
 
 // You are allowed to change this function
-function convertToUSD(price) {}
+
+const CONVERSION_FEE = 0.02;
+const CONVERSION_RATE_EUR_USD = 1.09;
+const CONVERSION_RATE_EUR_BRL = 5.6;
+const CONVERSION_RATE_EUR_YEN = 155.6;
+
+function formatCurrency(num: number): string{
+    return num.toFixed(2);
+}
+function addFee(price: number): number{
+    return price + price * CONVERSION_FEE;
+}
+function convertCurrency(price: number,rate: number): number {
+    return price * rate;
+}
 // You are allowed to change this function
-function convertToBRL(price) {}
+
 
 const product = "You don't know JS";
 const price = 12.5;
-const priceInUSD = convertToUSD(price);
-const priceInBRL = convertToBRL(price);
+const convertedToUSD = convertCurrency(price, CONVERSION_RATE_EUR_USD);
+const priceInUSD = formatCurrency(addFee(convertedToUSD));
+const priceInBRL = formatCurrency(addFee(convertCurrency(price, CONVERSION_RATE_EUR_BRL)));
 
 console.log("Product: " + product);
 console.log("Price: $" + priceInUSD);
diff --git a/src/20-arrays.ts b/src/20-arrays.ts
index 4ad8c88..ece6d4c 100644
--- a/src/20-arrays.ts
+++ b/src/20-arrays.ts
@@ -8,4 +8,9 @@ export {};
  *  - https://javascript.info/array
  */
 
-console.log(stringToArray(["John Doe"])); // Expected output: ['John', 'Doe']
+function stringToArray(fullName: string): string[] {
+  return fullName.split(" ");
+}
+
+const nameArray = stringToArray("John Doe");
+console.log(nameArray); // Expected output: ['John', 'Doe']
diff --git a/src/21-map.ts b/src/21-map.ts
index 5e5f020..a4ab7a2 100644
--- a/src/21-map.ts
+++ b/src/21-map.ts
@@ -1,16 +1,15 @@
 export {};
 
-function tidyUpString(str) {
-  return str
-    .trim()
-    .toLowerCase()
-    .replace("/", "");
+function tidyUpString(str: string): string {
+  return str.trim().toLowerCase().replace("/", "");
 }
 
 // You are allowed to edit this function
-function capitalise(str) {}
+function capitalise(str: string): string {
+  return str.charAt(0).toUpperCase() + str.slice(1);
+}
 
 const mentors = ["/Daniel ", "irina ", " Gordon", "ashleigh "];
-let mentorsTidy; // You are allowed to edit this line
+let mentorsTidy = mentors.map((mentor) => capitalise(tidyUpString(mentor))); // You are allowed to edit this line
 
 console.log(mentorsTidy); // Expected output: ["Daniel", "Irina", "Gordon", "Ashleigh"]
diff --git a/src/22-sort.ts b/src/22-sort.ts
index b5b19a2..27f9357 100644
--- a/src/22-sort.ts
+++ b/src/22-sort.ts
@@ -1,6 +1,7 @@
 export {};
 
 const letters = ["a", "n", "c", "e", "z", "f"];
-let sortedLetters; // You are allowed to change only this line
+let sortedLetters = [...letters].sort(); // You are allowed to change only this line
 
 console.log(sortedLetters); // Expected output: [ 'a', 'c', 'e', 'f', 'n', 'z' ]
+ 
\ No newline at end of file
diff --git a/src/23-min-max.ts b/src/23-min-max.ts
index 153eaf4..c6ba65b 100644
--- a/src/23-min-max.ts
+++ b/src/23-min-max.ts
@@ -5,9 +5,29 @@ export {};
  * one of which does not use built-in Math methods.
  */
 
-const min = array => {};
+const min = (array: any) => {
+  let min = array[0];
+  for (let i = 1; i < array.length; i++) {
+    if (array[i] < min) {
+      min = array[i];
+    }
+  }
+  return min;
+};
 
-const max = array => {};
+const max = (array: any) => {
+  let max = array[0];
+  for (let i = 1; i > max; i++) {
+    if (array[i] > max) {
+      max = array[i];
+    }
+  }
+  return max;
+};
+{
+    const min = (array: any) => Math.min(...array);
+    const max = (array: any) => Math.max(...array);
+}
 
 console.log(min([1, 2, 3, 4, 5])); // Expected output: 1
 console.log(min([9, -3, 6])); // Expected output: -3
diff --git a/src/24-looping-with-conditions.ts b/src/24-looping-with-conditions.ts
index a4cbfd1..8794355 100644
--- a/src/24-looping-with-conditions.ts
+++ b/src/24-looping-with-conditions.ts
@@ -1,5 +1,7 @@
 export {};
 
-function onlyTheAces(arr) {}
+function onlyTheAces(arr: string[]): string[] {
+    return arr.filter(element => element === "Ace");
+}
 
 console.log(onlyTheAces(["Ace", "King", "Queen", "Jack", "Ace"])); // Expected result: ['Ace', 'Ace']
diff --git a/src/25-calculator.ts b/src/25-calculator.ts
index 87e062d..3a75d15 100644
--- a/src/25-calculator.ts
+++ b/src/25-calculator.ts
@@ -1,14 +1,41 @@
 export {};
 
-function add() {}
+function add(a: number, b: number): number {
+  return a + b;
+}
 
-function subtract() {}
+function subtract(a: number, b: number): number {
+  return a - b;
+}
+
+function sum(num: number[]): number {
+  let sum = 0;
+  for (let i = 0; i < num.length; i++) {
+    sum += num[i];
+  }
+  return sum;
+}
+const result = sum([1,2,3]);
+
+
+
+
+function multiply(num: number[]): any {
+    let result = 1;
+    for (let i = 0; i < num.length; i++){
+       result *= num[i];
+    }
+    return result;
+   
+}
+
+function power(a: number, b: number): number {
+    return Math.pow(a,b);
+}
+const output = power(2,3);
 
-function sum() {}
 
-function multiply() {}
 
-function power() {}
 
 console.log(add(1, 2)); // Expected output: 3
 console.log(subtract(1, 2)); // Expected output: -1
diff --git a/src/26-validation.ts b/src/26-validation.ts
index 6b733e6..b1af83a 100644
--- a/src/26-validation.ts
+++ b/src/26-validation.ts
@@ -11,14 +11,24 @@ export {};
 const excludedNums = [6, 14, 91, 111];
 
 // You are allowed to edit only this function
-function validate(num) {}
+function validate(value: any): any {
+  return (
+    typeof value === "number" &&
+    Number.isInteger(value) && 
+    !excludedNums.includes(value)
+    );
+}
 
 console.log(validate(6));
 console.log(validate(10.5));
 console.log(validate(101));
 console.log(validate(-91));
 console.log(validate("16"));
-
+console.log(validate(true)); //falce)
+console.log(validate([4, "34"])); //falce
+console.log(validate(null)); //falce
+console.log(validate({})); //falce
+console.log(validate(() =>{})); //falce
 /* 
   Expected output:
   
diff --git a/src/27-slice.ts b/src/27-slice.ts
index 9d55cc3..91d3fb7 100644
--- a/src/27-slice.ts
+++ b/src/27-slice.ts
@@ -4,6 +4,9 @@ export {};
  * Write function first5 which returns first five elements from the array
  */
 
+function first5(arr: number[]): number[] {
+  return arr.slice(0, 5);
+}
 const numbers = [1, 2, 3, 4, 5, 6, 7, 8]; // You are NOT allowed to edit this line
 const first5Numbers = first5(numbers); // You are NOT allowed to edit this line
 
diff --git a/src/28-for-loops.ts b/src/28-for-loops.ts
index a9c6b2a..669a2a1 100644
--- a/src/28-for-loops.ts
+++ b/src/28-for-loops.ts
@@ -9,12 +9,21 @@ export {};
  *  - https://www.youtube.com/watch?v=Kn06785pkJg (JavaScript Loops Made Easy)
 */
 
-function goThroughNumbers(start, end) {}
+function goThroughNumbers(start: number, end: number): void {
+    if(start > end) {
+        console.log("invalid input");
+        return;
+    }
+    for(let i = start; i <= end; i++){
+        console.log(`> ${i} - ${i % 2 === 0 ? 'even' : 'odd'}`);
+    }
+    console.log("==============")
+}
 
 goThroughNumbers(3, 7);
 /* Expected output:
 
-    > 3 - odd
+    > 3 - odd 
     > 4 - even
     > 5 - odd
     > 6 - even
diff --git a/src/29-draw-triangle.ts b/src/29-draw-triangle.ts
index 994e3e8..d05c85c 100644
--- a/src/29-draw-triangle.ts
+++ b/src/29-draw-triangle.ts
@@ -5,8 +5,13 @@ export {};
  *  - https://blog.codeanalogies.com/2017/11/07/javascript-for-loops-explained/
  */
 
-function draw() {}
-
+function draw(n: number): any {
+  let i = 0;
+  i <= 3;
+  for (let i = 1; i <= 3; i++) {
+   console.log(" * " + i);
+  }
+}
 draw(3);
 /* Expected output:
 
@@ -14,9 +19,16 @@ draw(3);
     **
     ***
 
-*/
+*/ console.log("===================");
 
-draw(5);
+function draw1(n: number): any {
+  let j = 0;
+  j <= 5;
+  for (let j = 1; j <= 5; j++) {
+    console.log(" * " + j);
+  }
+}
+draw1(5);
 /* Expected output:
 
     *
diff --git a/src/30-objects.ts b/src/30-objects.ts
index b166fc8..1ab1e11 100644
--- a/src/30-objects.ts
+++ b/src/30-objects.ts
@@ -8,18 +8,28 @@ export {};
  * Luckily they're not so difficult to learn. As always w3schools will help:
  *  - https://www.w3schools.com/js/js_objects.asp
  */
-
-const books = [
+type Book = { author?: string; title: string; year?: number; pageCount?: number, publisher?: string };
+const books: Book[] = [
   {
     title: "4 hour work week",
     author: "Tim Ferris"
   },
   {
     title: "Tools of Titans",
-    author: "Tim Ferris"
+    author: "Tim Ferris",
+    year: 1998,
+    pageCount: 309,
+    publisher: 'Zvaigzne'
+  },
+  {
+    title: "Tools of Titans",
+    year: 1998,
+    pageCount: 309,
+    publisher: 'Zvaigzne'
+
   }
 ];
 
-const getTheTitles = () => {};
+const getTheTitles = (books: Book[]) => books.map((book: Book) => book.title);
 
 console.log(getTheTitles(books)); // Expected output: ['4 hour work week', 'Tools of Titans']
diff --git a/src/31-writers.ts b/src/31-writers.ts
index 2923e5f..6fa1038 100644
--- a/src/31-writers.ts
+++ b/src/31-writers.ts
@@ -11,27 +11,34 @@ const writers = [
     lastName: "Woolf",
     occupation: "writer",
     age: 59,
-    alive: false
+    alive: false,
   },
   {
     firstName: "Zadie",
     lastName: "Smith",
     occupation: "writer",
     age: 41,
-    alive: true
+    alive: true,
   },
   {
     firstName: "Jane",
     lastName: "Austen",
     occupation: "writer",
     age: 41,
-    alive: false
+    alive: false,
   },
   {
     firstName: "bell",
     lastName: "hooks",
     occupation: "writer",
     age: 64,
-    alive: true
-  }
+    alive: true,
+  },
 ];
+writers.forEach((writer) => {
+  if (writer.alive) {
+    console.log(
+      `Hi, my name is ${writer.firstName} ${writer.lastName}.I am ${writer.age} years old, and work as a ${writer.occupation}. `
+    );
+  }
+});
diff --git a/src/32-reading-status.ts b/src/32-reading-status.ts
index f64ec18..99e9c34 100644
--- a/src/32-reading-status.ts
+++ b/src/32-reading-status.ts
@@ -1,24 +1,36 @@
 export {};
-
-const library = [
+interface Book {
+  title: string;
+  author: string;
+  isRead: boolean;
+}
+const library: Book[] = [
   {
     title: "The Road Ahead",
     author: "Bill Gates",
-    isRead: true
+    isRead: true,
   },
   {
     title: "Steve Jobs",
     author: "Walter Isaacson",
-    isRead: true
+    isRead: true,
   },
   {
     title: "Mockingjay: The Final Book of The Hunger Games",
     author: "Suzanne Collins",
-    isRead: false
-  }
+    isRead: false,
+  },
 ];
 
-const showStatus = () => {};
+const showStatus = (library: Book[]) => {
+  library.forEach((book: Book) => {
+    if (book.isRead) {
+      console.log(`Already read '${book.title}' by ${book.author}. `);
+    } else {
+      console.log(`You still need to read '${book.title}' by ${book.author}.`);
+    }
+  });
+};
 
 showStatus(library);
 
diff --git a/src/33-temperature-conversion.ts b/src/33-temperature-conversion.ts
index 180fdfa..e95b6bf 100644
--- a/src/33-temperature-conversion.ts
+++ b/src/33-temperature-conversion.ts
@@ -14,8 +14,19 @@ export {};
  * Temperature should be rounded to one decimal place: i.e., fahrenheitToCelsius(100) should return 37.8 and not 37.77777777777778.
  */
 
-const fahrenheitToCelsius = ?
-const celsiusToFahrenheit = ?
+/*const fahrenheitToCelsius = (fahrenheit: number) => {
+  return parseFloat((((fahrenheit - 32) * 5) / 9).toFixed(1));
+};
+const celsiusToFahrenheit = (celsius: number) => {
+  return parseFloat(((celsius * 5) / 9 + 32).toFixed(1));
+  ======================================================== */
+
+const fahrenheitToCelsius = (fahrenheit: number) => {
+  return Math.round((((fahrenheit - 32) * 5) / 9) * 10);
+};
+const celsiusToFahrenheit = (celsius: number) => {
+  return Math.round(((celsius * 9) / 5 + 32) * 10) / 10;
+};
 
 console.log(fahrenheitToCelsius(32)); // Expected result: 0
 console.log(celsiusToFahrenheit(0)); // Expected result: 32
diff --git a/src/34-protect-email.ts b/src/34-protect-email.ts
index 64303ae..6d9c0a8 100644
--- a/src/34-protect-email.ts
+++ b/src/34-protect-email.ts
@@ -3,6 +3,12 @@ export {};
 /**
  * Create a function protectEmail which hides some symbols of the email
  */
+function protectEmail(email: string) {
+    const [user, domain] = email.split("@");
+    let protectedUser = user.length > 2 ? user.slice(0, Math.min(user.length - 1, 3)) + "..." : "...";
+    return `${protectedUser}@${domain}`;
+
+}
 
 console.log(protectEmail("secret123@codelex.io")); // Expected result: sec...@codelex.io
 console.log(protectEmail("example@example.com")); // Expected result: exa...@example.com
diff --git a/src/35-sum-all.ts b/src/35-sum-all.ts
index 0c6a145..54462fa 100644
--- a/src/35-sum-all.ts
+++ b/src/35-sum-all.ts
@@ -6,6 +6,13 @@ export {};
  *  - 1, 4 will return 1 + 2 + 3 + 4 which is 10
  */
 
-const sumAll = function() {};
+let sumAll = [1, 2, 3, 4];
 
-console.log(sumAll(1, 4)); // Expected output: 10
+function sumNumbers(array: number[]){
+  let sum = 0;
+  for (let i = 0; i < array.length; i++) {
+    sum += array[i];
+  }
+  return sum;
+}
+console.log(sumNumbers(sumAll));
diff --git a/src/36-pythagorean-theorem.ts b/src/36-pythagorean-theorem.ts
index 11ebd41..dcfe6ce 100644
--- a/src/36-pythagorean-theorem.ts
+++ b/src/36-pythagorean-theorem.ts
@@ -10,7 +10,10 @@ export {};
  * and name them in your function accordingly.
  */
 
-const pythagoreanTheorem = () => {};
+const pythagoreanTheorem = (a: number, b: number): number  => {
+    return Math.sqrt(a * a + b * b);
+
+};
 
 console.log(pythagoreanTheorem(2, 4)); // Expected result: 4.47213595499958
 console.log(pythagoreanTheorem(3, 4)); // Expected result: 5
diff --git a/src/37-indexOf.ts b/src/37-indexOf.ts
index 9e71925..48fed72 100644
--- a/src/37-indexOf.ts
+++ b/src/37-indexOf.ts
@@ -8,7 +8,14 @@ export {};
  */
 
 // You are allowed to edit only this function
-function remove(arr, valueToRemove) {}
+function remove(arr: any, valueToRemove: any) {
+  const index = arr.indexOf(valueToRemove);
+  if(index === -1){
+    return arr.slice();
+  }
+  return[...arr.slice(0,index), ...arr.slice(index + 1)];
+
+}
 
 const numbers = [1, 2, 3];
 const names = ["John", "Alice", "Ellen"];
diff --git a/src/38-remove-from-array.ts b/src/38-remove-from-array.ts
index 10497a0..4bb8791 100644
--- a/src/38-remove-from-array.ts
+++ b/src/38-remove-from-array.ts
@@ -1,6 +1,11 @@
 export {};
 
-const removeFromArray = function() {};
+//const removeFromArray = function() {};
+
+const removeFromArray = function (number: number[], ...restNums: number[]): number[]
+{
+    return number.filter (number => !restNums.includes(number) )
+};
 
 console.log(removeFromArray([1, 2, 3, 4], 3)); // Expected output: [1, 2, 4]
 console.log(removeFromArray([1, 2, 3, 4], 7)); // Expected output: [1, 2, 3, 4]
diff --git a/src/39-string-occurences.ts b/src/39-string-occurences.ts
index 3468820..17c6732 100644
--- a/src/39-string-occurences.ts
+++ b/src/39-string-occurences.ts
@@ -1,6 +1,10 @@
 export {};
 
-const count = () => {};
+const count = (text: string, word: string) => {
+    const regex = new RegExp(`\\b${word}\\b`, 'gi');
+    const matches = text.match(regex);
+    return matches ? matches.length : 0;
+};
 
 console.log(count("The quick brown fox jumps over the lazy dog", "the")); // Expected output: 2
 console.log(count("The quick brown fox jumps over the lazy dog", "fox")); // Expected output: 1
diff --git a/src/40-multiply-map.ts b/src/40-multiply-map.ts
index d7f8e6b..0c0f633 100644
--- a/src/40-multiply-map.ts
+++ b/src/40-multiply-map.ts
@@ -8,10 +8,19 @@ export {};
  * and recreate the logic yourself.
  */
 
-const map = () => {};
+/*const map = (
+  array: number[],
+  transform: (value: number, index: number, array: number[]) => number
+) => {
+  let result = [];
+  for (let i = 0; i < array.length; i++) {
+    result.push(transform(array[i], i, array));
+  }
+  return result;
+};
 
 const numbers = [1, 2, 3];
-const doubled = map(numbers, function(number) {
+const doubled = map(numbers, function (number) {
   return number * 2;
 });
-console.log(doubled); // Expected result: [2, 4, 6]
+console.log(doubled); // Expected result: [2, 4, 6]*/