What am I?

In a boat, the father of a sailor's son is sitting with the son of the sailor. However, the sailor is not present on the boat.

Can this even be possible?

If "P" means "-", "Q" means "/", "R" means "+", and "S" means "*" then find the value of the following:

21 Q 7 R 9 S 10 P 13

You can win me and lose me but never buy me
You can not eat me and never want to part with me
I can make you cry or bring you joy
I am not a machine and definitely not a toy
You keep me but i am not forever just yours
You might find me in a case or on a shelf next to a vase
I am hard and i am tall if you bump me i am sure to fall
I am made of different materials and am at many events
If your lucky and fight hard I might be yours
What am I ?

Why Aeroplane windows are round?

If you say my name, I will no longer exist. What am I?

What is the fastest way to double your money?

I know a nine-letter word having only one vowel.
Do you ?

What kind of band never plays music?

A seven-year-old kid challenged his classmates that he can make the number one disappear by adding something to it.

How can he do that?