Our product and our sum always give the same answer. Who are we?

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

O T T F F S S ?

They are the five precious gems of an everyday sort and all can be found on a Tennis Court. Who are they?

You Throw The Outside, Cook The Inside
Eat The Outside, Throw The Inside.

What Is It?

The day before yesterday I was 25 and the next year I will be 28. This is true only one day in a year. What day is my birthday?

There are two arch enemies Messi and Ronaldo who hate each other to an extreme. One day both were going together and a Jeanie appeared in front of them. Jeanie grants 3 wishes to Ronaldo and one to Messi.

Messi replied smartly 'Give me twice whatever Ronaldo demands'.

Ronaldo asked his 1st wish 'Give me 10000 billion dollars. Soon Messi gets 2000 billion dollars.
Ronaldo asked for his 2nd wish 'Give me one mansion in every country in the world. Soon Messi gets two mansions in every country of the world?

What should be Ronaldo's third wish?

In a chess board, the queen piece can move horizontally, vertically and diagonally freely. The picture represents the same.Can you place 8 queens on the board in a manner that none of the queens can attack each other?

No matter how little or how much you use me, you change me every month. What am I?

There are three boxes which are labeled as Rs100, Rs150, and Rs200. One box contains two notes of Rs. 50. The second box contains one note of Rs50 and one note of Rs100 The third box contains two Rs. 100 notes. All boxes are labeled incorrectly.

What is the minimum number of boxes you must check in order to label all boxes correctly?

If 2 workers can complete painting 2 walls in exactly 2 hours.

How many workers would be needed to paint 18 walls in 6 hours?