What has one letter and starts with an E?

A boy was locked in a room by some robbers. All that is in the room is a piano, a calendar, and a bed. The room is locked from the outside. What does he eat, drink, and how does he escape and get out?

what's the probability of getting a king or a queen from a pack of 52 cards?

I came first on earth but second on the heaven.
I also came twice in a week but found just once in a year.
I stay away from months but you can find me in February.

What am I?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?

Can you figure out the logic I used to decide the order of the following words:
gun, shoe, spree, door, hive, kicks, heaven, gate, line, den

What can you see in the middle of March and April that you can never see in any other month?

Who can jump higher than a Mountain?