How do you go from 98 to 720 using just one letter?

Count the number of lines in the image below ?

You walk into an old horror house. It has no power or plumbing. Once inside, you see three doors. Each door has a number on it. Behind each door is a way for you to die. Behind door number one, you die by getting eaten by a lion. Behind door number two, you die by getting murdered. Behind door number three, you die by an electric chair. You can’t turn back, so you have to go through a door. Which door do you go through?

A shepherd had 18 sheep, out of which, all but ten died.

Can you tell us how many sheep was he left with?

What is black when you buy it, red when you use it, and gray when you throw it away?

Solve below popular number sequence
314 159 265 358 979 323 846 ?

Can it be possible to build a house that has all its four walls facing towards the South?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

Can you find a seven digit number which describes itself. The first digit is the number of zeros in the number. The second digit is the number of ones in the number, etc. For example, in the number 21200, there are 2 zeros, 1 one, 2 twos, 0 threes and 0 fours.

A father's child, a mother's child, yet no one's son.

Who am I?