diff --git a/src/challenge.ts b/src/challenge.ts
index 63a7766..86803f1 100644
--- a/src/challenge.ts
+++ b/src/challenge.ts
@@ -9,6 +9,7 @@
 // logger<number | string>([1, 2, 3, "one", "two", "three"]);
 function logger<T>(array: T[]): void {
   // write your code here...
+  array.forEach((element) => console.log(element));
 }
 
 // `toCelsius` function that:
@@ -19,8 +20,7 @@ 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...
-
-  return []; // replace empty array with what you see is fit
+  return temperatures.map((temps) => (temps - 32) * (5 / 9)); // replace empty array with what you see is fit
 }
 
 // `hottestDays` function that:
@@ -32,8 +32,7 @@ function toCelsius(temperatures: number[]): number[] {
 // hottestDays([80, 90, 100, 110], 95); // => [100, 110]
 function hottestDays(temperatures: number[], threshold: number): number[] {
   // write your code here...
-
-  return []; // replace empty array with what you see is fit
+  return temperatures.filter((temps) => temps > threshold); // replace empty array with what you see is fit
 }
 
 // `logHottestDays` function that:
@@ -42,6 +41,7 @@ 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...
+  logger(toCelsius(hottestDays(temperatures, threshold)));
 }
 
 export { logger, toCelsius, hottestDays, logHottestDays };
diff --git a/src/filtering.ts b/src/filtering.ts
index 49411d8..826773e 100644
--- a/src/filtering.ts
+++ b/src/filtering.ts
@@ -11,8 +11,7 @@ const numbers = [10, 13, 20, 25, 38, 35, 40];
 // greaterThanTwentyFive(numbers); // => [38, 35, 40]
 function greaterThanTwentyFive(numbers: number[]): number[] {
   // write your code here...
-
-  return []; // replace empty array with what you see is fit
+  return numbers.filter((num) => num >= 25); // replace empty array with what you see is fit
 }
 
 // `divisibleByFive` function that:
@@ -22,8 +21,7 @@ function greaterThanTwentyFive(numbers: number[]): number[] {
 // divisibleByFive(numbers); // => [10, 20, 25, 35, 40]
 function divisibleByFive(numbers: number[]): number[] {
   // write your code here...
-
-  return []; // replace empty array with what you see is fit
+  return numbers.filter((num) => num % 5 === 0); // replace empty array with what you see is fit
 }
 
 export { greaterThanTwentyFive, divisibleByFive };
diff --git a/src/mapping+filtering.ts b/src/mapping+filtering.ts
index 269ad83..eb723ef 100644
--- a/src/mapping+filtering.ts
+++ b/src/mapping+filtering.ts
@@ -11,8 +11,7 @@ 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...
-
-  return []; // replace empty array with what you see is fit
+  return numbers.filter((num) => num >= 20).map((num) => Math.pow(num, 2)); // replace empty array with what you see is fit
 }
 
 // `filteredAndTripled` function that:
@@ -22,8 +21,7 @@ function filteredAndSquared(numbers: number[]): number[] {
 // filteredAndTripled(numbers); // => [30, 60, 75, 105, 120]
 function filteredAndTripled(numbers: number[]): number[] {
   // write your code here...
-
-  return []; // replace empty array with what you see is fit
+  return numbers.filter((num) => num % 5 === 0).map((num) => num * 3); // replace empty array with what you see is fit
 }
 
 export { filteredAndSquared, filteredAndTripled };
diff --git a/src/mapping.ts b/src/mapping.ts
index 6f18eef..e7347f2 100644
--- a/src/mapping.ts
+++ b/src/mapping.ts
@@ -11,8 +11,7 @@ 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...
-
-  return []; // replace empty array with what you see is fit
+  return numbers.map((num) => Math.pow(num, 2)); // replace empty array with what you see is fit
 }
 
 // `doubledNumbers` function that:
@@ -22,8 +21,7 @@ function squaredNumbers(numbers: number[]): number[] {
 // doubledNumbers(numbers); // => [20, 26, 40, 50, 76, 70, 80]
 function doubledNumbers(numbers: number[]): number[] {
   // write your code here...
-
-  return []; // replace empty array with what you see is fit
+  return numbers.map((num) => num * 2); // replace empty array with what you see is fit
 }
 
 export { squaredNumbers, doubledNumbers };