Fun Riddles

Question: How many letters are in the answer to this riddle?

Question: I'm not a pool, a tree, a slave, a website, or a shirt.

What am I?

Question: It takes ten men ten hours to build a certain wall. How long does it take five men to build the same wall?

Question: What is brown and sticky?

Question: Wednesday, Tom and Joe went to a restaurant and ate dinner. When they were done they paid for the food and left. But Tom and Joe didn't pay for the food.

Who did?