The five sons

Question: I am the first son of my father, I can live without men but men can't live without me, the second son of my father has seen men rise and fall and have all of their secrets in his belly, the third son of my father can never give you his gift forever, he takes it from you when you corrupt it unknowingly but men cry for his gift no matter its cost, the fourth son of my father is an obedient servant in the hands of men but when he losses his master he becomes an unmercifully god, the fifth son of my father is the center of our lives, he guides us but he is a divine mystery. What are we?

Question: A girl dove in the sea.. some say there are two people under the sea. Why is that?

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.