What goes up but never comes down?

I am a five-letter word and comprises two different vowels and three same consonants. I am so strong that I can spoil your entire work.

Can you find out who am I?

Is the statement valid that it does not matter how much older a sibling is, eventually the younger one will be half as old as the older one?

There are are five things wrong with this sentence; only geniuses will be able to to spot all of the mitstakes

Kohli and Dhoni decided to have a paintball match.
Kohli told Dhoni, "Sir it is not right as you got thrice the paintballs I have".

Dhoni instantly gives Kohli 10 hit paintballs.
Kohli replied, "Sir, I believe you still have twice the paintballs than I have".

Dhoni gives "?" more paintballs to Kohli.
Kohli replied, "Sir it is even now, Let us have a match".

What is "?".

In the picture, you can see a chess board. On the top left position, the K marks a knight. Now, can you move the knight in a manner that after 63 moves, the knight has been placed at all the squares exactly once excluding the starting square?

Which is faster, Heat or Cold ? Explain.

Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?

I am a number I am not an odd number I am higher than 90 I am not higher than 100 If you subtract me from 100, you get nothing. What number am I?

Find the missing number in the sequence below: