diff --git a/index.js b/index.js
index 294f6b2..9dfa4e4 100644
--- a/index.js
+++ b/index.js
@@ -8,12 +8,11 @@ const s4 = "bread";
 const s5 = "and";
 
 // Concatenate the string variables into one new string
-
+const firstConcat = s1 + " " + s2 + " " + s3 + " " + s4;
+let tongueTwister = firstConcat + " " + s5 + " " + firstConcat;
 
 // Print out the concatenated string
-
-
-
+console.log(tongueTwister);
 
 /*******************************************
     Iteration 1.2 | Camel Tail
@@ -22,37 +21,33 @@ const part1 = "java";
 const part2 = "script";
 
 // Convert the last letter of part1 and part2 to uppercase and concatenate the strings
-
-
+result =
+  part1.slice(0, -1) +
+  part1.slice(-1).toUpperCase() +
+  part2.slice(0, -1) +
+  part2.slice(-1).toUpperCase();
 // Print the cameLtaiL-formatted string
-
-
-
-
+console.log(result);
 /*******************************************
     Iteration 2.1 | Calculate Tip
 *******************************************/
 const billTotal = 84;
 
 // Calculate the tip (15% of the bill total)
-
-
+const tipAmount = billTotal * (15 / 100);
 // Print out the tipAmount
-
-
-
-
+console.log(tipAmount);
+console.log(
+  `We recommend to give ${tipAmount}€ as a tip for a bill of ${billTotal}€.`
+);
 /*******************************************
     Iteration 2.2 | Generate Random Number
 *******************************************/
 
 // Generate a random integer between 1 and 10 (inclusive)
-
-
+const randomNumber = Math.floor(Math.random() * 10 + 1);
 // Print the generated random number
-
-
-
+console.log(randomNumber);
 /*******************************************
     Iteration 3.1 | Booleans
 *******************************************/
@@ -62,15 +57,23 @@ const b = false;
 
 // Try and guess the output of the below expressions first and write your answers down:
 const expression1 = a && b;
-
+// false
+console.log(`I say false, expression 1 is ${expression1}`);
 const expression2 = a || b;
-
+// true
+console.log(`I say true, expression 2 is ${expression2}`);
 const expression3 = !a && b;
-
+// false
+console.log(`I say false, expression 3 is ${expression3}`);
 const expression4 = !(a && b);
-
+// true
+console.log(`I say true, expression 4 is ${expression4}`);
 const expression5 = !a || !b;
-
+// true
+console.log(`I say true, expression 5 is ${expression5}`);
 const expression6 = !(a || b);
-
-const expression7 = a && a;
\ No newline at end of file
+// false
+console.log(`I say false, expression 6 is ${expression6}`);
+const expression7 = a && a;
+// true
+console.log(`I say true, expression 7 is ${expression7}`);