I have eight fingers and two thumbs but I do not live. What Am I?

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

The following four words might seem abrupt to you. But you can make them meaningful by just adding vowels.
RDSH
GGPLNT
TMT
NN

Hint: All of them are vegetables.

Solve the puzzle by telling what does below picture means.

Can you count the number of quadrilaterals in the picture below?

When my father was 31 I was 8. Now he is twice as old as me. How old am I?

What is the difference between a jeweller and a jailer?

I have branches, but no fruit, trunk or leaves. What am I?

A time long back, there lived a king who ruled the great kingdom of Trojan House. As a part of the renovation of the kingdom to meet future security needs, he asked his chief architect to lay down a new play in a manner that all of his 10 castles are connected through five straight walls and each wall must connect four castles together. He also asked the architect that at least one of his castles should be protected with walls. The architect could not come up with any solution that served all of King's choices, but he suggested the best plan that you can see in the picture below. Can you find a better solution to serve the king's demand?

How can you make the following equation true by drawing only one straight line: 5+5+5=550 ?