I travel all around the world but always stay in the corner. What am I?

A frog is at the bottom of a 30-meter well. Each day he summons enough energy for one 3-meter leap up the well. Exhausted, he then hangs there for the rest of the day. At night, while he is asleep, he slips 2 meters backwards. How many days does it take him to escape from the well?

Mr Red Lives in the red house.
Mr Green Lives in the greenhouse.
Mr Yellow Lives in the yellow house.

Who lives in the Whitehouse?

Can you find the ages of a son, father and grandfather based on the following facts?
The sum of the ages of grandfather, father and son is 140 years.
The age of the son in months is the same as the grandfather in years.
The age of the son in days is the same as the father in weeks.

They came out at night, without being called.
They lost at day, without being stolen.
Who are they?

What is the word or phrase below?
R | E | A | D

How many cubic feet of dirt are in a hole of one foot deep, three feet long, and two feet wide?

Can you decipher these quotes by Albert Einstein?
Blf xzm mvevi hloev z kilyovn lm gsv ovevo lm dsrxs rg dzh xivzgvw.

Remove two matchsticks to make the below equation correct.

The person who makes it has no need for it. He who purchases it does not use it. The person who does use it does not know they are. What is it?