What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?

There are five vowels (a, e, i, o, u) in the English language.
Can you tell us a word that contains all these vowels?

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

If it took eight men ten hours to build a wall, how long would it take four men to build it?

I have two coins.
* One of the coins is a faulty coin having a tail on both sides of it.
* The other coin is a perfect coin (heads on side and tail on other).

I blindfold myself and pick a coin and put the coin on the table. The face of the coin towards the sky is the tail.

What is the probability that another side is also tail?

What two things can you never eat for breakfast?

What goes up but never comes down?

There are six people in a family namely M, N, O, P, Q and R.

R and O are brother and sister.

N is the brother of Q's husband.
P is the father of M and grandfather of R.

How many male members are in the family?

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

What can go through glass without breaking it?