I’m tall when I’m young, and I’m short when I’m old. What am I?

There is a shop where written:
Buy 1 for $1
10 for $2
100 for $3
I needed 999 and still only paid $3. How could this be financially viable for the shop-keeper?

In the picture given below, can you find out which digit will take place of the question mark?

The doctor prescribed you to take one pill from the bottle every half an hour. The bottle is now left with only three pills.

How long do you think you have before you run out of pills?

Three brothers Jacob, John, and James live in Mexico City. The product of the ages of these brothers is 175. Jacob and John are twins. How old is James?

Most people think of me as money. But when they find me in the water, they won’t get any money out of me. What am I?

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

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

It has horns but can’t beep. It is like to bleat but It is not a sheep. What is it?

A man in a car saw a Golden Door, Silver Door and a Bronze Door. What door did he open first?