Answer:
If four people can repair four bicycles in four hours, how many bicycles can eight people repair in eight hours?
What is flat, usually square, and made from trees but isn't wood?
I weaken all men for hours each day. I show you strange visions while you are away. I take you by night, by day take you back. None suffer to have me, but do from my lack.
It get wetter and wetter the more it dries
You can find me inside your body but not below the waist or in your tummy. I am located in the upper part and I am a symbol of love.
My days are numbered. What am I?