diff --git a/01/app.js b/01/app.js
index e69de29..5c339f9 100644
--- a/01/app.js
+++ b/01/app.js
@@ -0,0 +1,5 @@
+const users = ['Jan Kowalski', 'Anna Polsza', 'Radek Kozak', 'Michał Radwan', "Katarzyna Jarek"];
+
+console.log(users[0], users[2], users[4]);
+
+console.log(users.length);
\ No newline at end of file
diff --git a/02/app.js b/02/app.js
index 9ad302b..e183155 100644
--- a/02/app.js
+++ b/02/app.js
@@ -1,6 +1,19 @@
 const randomArray = createRandomArray();
 console.log(randomArray);
 
+for (let i = 0; i < randomArray.length; i++) {
+    console.log(randomArray[i]);
+}
+
+randomArray.forEach(function (item) {
+    console.log(item);
+});
+
+const lastIndex = randomArray.length - 1;
+
+console.log(randomArray[lastIndex])
+
+
 
 
 // nie modyfikuj kodu poniżej!
@@ -11,13 +24,13 @@ console.log(randomArray);
 function createRandomArray() {
     const arr = [];
     const len = getRandomInteger(1, 10)
-    for(let i=0; i<len; i++) {
-        arr.push( getRandomInteger(1, 100) );
+    for (let i = 0; i < len; i++) {
+        arr.push(getRandomInteger(1, 100));
     }
 
     return arr;
 }
 
 function getRandomInteger(min, max) {
-    return Math.round(Math.random() * (max-min) + min);
+    return Math.round(Math.random() * (max - min) + min);
 }
\ No newline at end of file
diff --git a/03/app.js b/03/app.js
index cebcbc2..d4ab2d8 100644
--- a/03/app.js
+++ b/03/app.js
@@ -1,2 +1,10 @@
 const n = 24;
-const oddNumbers = [];
\ No newline at end of file
+const oddNumbers = [];
+
+for( let i=1; i<n; i++){
+    if(i % 2 === 1){
+        oddNumbers.push(i);
+    }
+}
+
+console.log(oddNumbers);
\ No newline at end of file
diff --git a/04/app.js b/04/app.js
index 8285afd..ab8d92f 100644
--- a/04/app.js
+++ b/04/app.js
@@ -1 +1,9 @@
-const years = [1980, 1934, 2002, 2019];
\ No newline at end of file
+const years = [1980, 1934, 2002, 2019];
+
+const currYear = (new Date()).getFullYear();
+
+const ages = years.map(function(item){
+    return currYear - item;
+});
+
+console.log(ages);
\ No newline at end of file
diff --git a/05/app.js b/05/app.js
index 1c6bb90..47462e1 100644
--- a/05/app.js
+++ b/05/app.js
@@ -1 +1,16 @@
-const numbers = [1, 2, 3, 4, 5, 6, 7];
\ No newline at end of file
+const numbers = [1, 2, 3, 4, 5, 6, 7];
+
+
+const evenNumbers = numbers.filter(isEven);
+
+console.log(evenNumbers);
+
+function isEven(num){
+    return num % 2 === 0;
+};
+
+const sum = evenNumbers.reduce(function(acc, curr){
+    return acc + curr;
+})
+
+console.log(sum);
\ No newline at end of file