What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?

What are the next two letters in the following series and why?
W A T N T L I T F S _ _

*Hint: Check Puzzle Title

Keyboard words are not in alphabetical order, Why?

How will you measure 15 minutes using two hourglasses of 7 minutes and 11 minutes respectively?

What is the end of everything?

You walk into a room where there are three primates held in their respective cages:
1) A lion who is eating the flesh of a goat.
2) An orangutan who is playing with blocks.
3) A donkey who is sitting idle.

Who is the most intelligent primate in the room?

We have shown you a regular water barrel as below. Without using any measuring device can you check if the barrel is more than half-filled or less than half-filled?

why number 8549176320 is one of a kind?

Prove that the below maths equation is true.

8 + 8 = 91

Before the start of the car race, John and Jacob have the same amount of fuel in their car. With this fuel, John can drive for 4 hours while Jacob can drive five hours.
After a time they realize that the amount of fuel left in John's car is 1/4th of the fuel in Jacob's.

For how long they are racing?