Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

By moving exactly three matchsticks can you make the below equation true.It can be solved by 3 ways.

If you read clockwise, you can form a word by inserting three missing letters in the picture given below. Can you do it?

How many cubic feet of dirt are in a hole of one foot deep, three feet long, and two feet wide?

If,
29 - 1 = 30
9 - 1 = 10
14 - 1 = 15

Based on similar logic, Can you prove that the below algebraic equation is true?
11 - 1 = 10 ?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

Through your logical capabilities, can you make 7 an even?

Luis Garavito killed Density x Volume.

Who is Luis Garavito ?

Vin Diesel is pulling a theft and has planned to run away with all the cash kept in the safe. But the only way to open the safe is the 13 character password. He has a set of five clues given to him by a trustworthy source.

Exactly two of the below statements are false.
The password is contained within this sentence.
The password is not in this hint.
The password is within only one of these statements.
At least one of the above statements is a lie.