diff --git a/src/challenge.ts b/src/challenge.ts
index 63a7766..e70f258 100644
--- a/src/challenge.ts
+++ b/src/challenge.ts
@@ -9,6 +9,9 @@
 // logger<number | string>([1, 2, 3, "one", "two", "three"]);
 function logger<T>(array: T[]): void {
   // write your code here...
+  array.forEach(x => {
+    console.log(x);
+  });
 }
 
 // `toCelsius` function that:
@@ -19,7 +22,10 @@ function logger<T>(array: T[]): void {
 // toCelsius([32, 68, 100, 212]); // => [0, 20, 37.7778, 100]
 function toCelsius(temperatures: number[]): number[] {
   // write your code here...
-
+  if (temperatures !== undefined){
+    let temperatures1: number[] = temperatures.map((num) => (num - 32) * (5/9));
+    return temperatures1;
+  }
   return []; // replace empty array with what you see is fit
 }
 
@@ -32,7 +38,10 @@ function toCelsius(temperatures: number[]): number[] {
 // hottestDays([80, 90, 100, 110], 95); // => [100, 110]
 function hottestDays(temperatures: number[], threshold: number): number[] {
   // write your code here...
-
+  if (temperatures !== undefined){
+    let temperatures1: number[] = temperatures.filter((num) => num > threshold);
+    return temperatures1;
+  }
   return []; // replace empty array with what you see is fit
 }
 
@@ -42,6 +51,10 @@ function hottestDays(temperatures: number[], threshold: number): number[] {
 // - Log temperatures that exceed the threshold to the console IN DEGREES CELSIUS  (hint: you can combine all previous functions)
 function logHottestDays(temperatures: number[], threshold: number): void {
   // write your code here...
+  if (temperatures !== undefined){
+    const hottestDaysVal = toCelsius(hottestDays(temperatures, threshold));
+    logger(hottestDaysVal);
+  }
 }
 
 export { logger, toCelsius, hottestDays, logHottestDays };
diff --git a/src/filtering.ts b/src/filtering.ts
index 49411d8..edbde19 100644
--- a/src/filtering.ts
+++ b/src/filtering.ts
@@ -11,7 +11,11 @@ const numbers = [10, 13, 20, 25, 38, 35, 40];
 // greaterThanTwentyFive(numbers); // => [38, 35, 40]
 function greaterThanTwentyFive(numbers: number[]): number[] {
   // write your code here...
-
+  if (numbers !== undefined){
+    let number1: number[] = numbers.filter((num) => num >= 25);
+    return number1;
+  }
+    
   return []; // replace empty array with what you see is fit
 }
 
@@ -22,7 +26,10 @@ function greaterThanTwentyFive(numbers: number[]): number[] {
 // divisibleByFive(numbers); // => [10, 20, 25, 35, 40]
 function divisibleByFive(numbers: number[]): number[] {
   // write your code here...
-
+  if (numbers !== undefined){
+    let number1: number[] = numbers.filter((num) => num %5 == 0);
+    return number1;
+  }
   return []; // replace empty array with what you see is fit
 }
 
diff --git a/src/mapping+filtering.ts b/src/mapping+filtering.ts
index 269ad83..ee8eaa4 100644
--- a/src/mapping+filtering.ts
+++ b/src/mapping+filtering.ts
@@ -11,7 +11,10 @@ const numbers = [10, 13, 20, 25, 38, 35, 40];
 // filteredAndSquared(numbers); // => [400, 625, 1444, 1225, 1600]
 function filteredAndSquared(numbers: number[]): number[] {
   // write your code here...
-
+  if (numbers !== undefined){
+    let number1: number[] = numbers.filter((num) => num >= 20).map(x => x * x);
+    return number1;
+  }
   return []; // replace empty array with what you see is fit
 }
 
@@ -22,7 +25,10 @@ function filteredAndSquared(numbers: number[]): number[] {
 // filteredAndTripled(numbers); // => [30, 60, 75, 105, 120]
 function filteredAndTripled(numbers: number[]): number[] {
   // write your code here...
-
+  if (numbers !== undefined){
+    let number1: number[] = numbers.filter((num) => num % 5 === 0).map(x => x * 3);
+    return number1;
+  }
   return []; // replace empty array with what you see is fit
 }
 
diff --git a/src/mapping.ts b/src/mapping.ts
index 6f18eef..0e34dfe 100644
--- a/src/mapping.ts
+++ b/src/mapping.ts
@@ -11,7 +11,10 @@ const numbers = [10, 13, 20, 25, 38, 35, 40];
 // squaredNumbers(numbers); // => [100, 169, 400, 625, 1444, 1225, 1600]
 function squaredNumbers(numbers: number[]): number[] {
   // write your code here...
-
+  if (numbers !== undefined){
+    let number1: number[] = numbers.map((num) => num * num);
+    return number1;
+  }
   return []; // replace empty array with what you see is fit
 }
 
@@ -22,7 +25,10 @@ function squaredNumbers(numbers: number[]): number[] {
 // doubledNumbers(numbers); // => [20, 26, 40, 50, 76, 70, 80]
 function doubledNumbers(numbers: number[]): number[] {
   // write your code here...
-
+  if (numbers !== undefined){
+    let number1: number[] = numbers.map((num) => num * 2);
+    return number1;
+  }
   return []; // replace empty array with what you see is fit
 }