Fix 5 typos
Lecture 04
Fix some typos
Merge pull request #29 from Monika-Ilieva/lecutre-02-conditions-arrays

Fix 5 typos
Fix indentation and typo
Merge pull request #30 from EmanuelaMollova/04-fix-typos

Fix some typos
Merge pull request #31 from NikolayGenov/04-fix-typos

Fix some typos and indentation