Logic Riddles

Question: Harry, the happy hippo, happily hopped from the hippo hospital. How many h's are in this sentence?

Question: There are two cars. The suburban is going 50 mph, and the mini van is going 30 mph. Although, the minivan passes the suburban and both cars are still going the same speed that they started at. How?

Question: A wooden block is floated on water. What can be placed on it to reduce its weight?

Question: 1 is 3, 3 is 5, 5 is 4, 4 is perfect. Why?

Question: What animal can jump higher than a house?