Math Riddles

Question: can you make an equation by using only the no.-4,4,4,4 whose answer will be 20.

Question: What is 50% divided by 2?

Question: Name 4 ways to calculate 1+1.

Question: You need a room for your group. Each person needs 5 square feet of space. You have 25 people in your group, what is the smallest room you can use?

Question: What exponents other than the same two numbers with the numbers one thru ten can be flipped and have the same answer?