What Am I?

Question: I can climb incredibly high, but only drop so low, it all depends how fast the little ones go....

Question: Surrounded by life , yet life is its biggest enemy. But without life there is no need for it to exist. What is it?

Question: During what month do people sleep the least?

Question: When is 99 more than 100?

Question: The more you add, the less it weighs.

Question: What makes a hotel hot even when below zero temperatures?