Good Riddles

Question: Filled with garb,
the price is free.
Just return what you don't need.

What am I?

Question: In what year did Christmas and New Year's fall on the same year?

Question: There was a window cleaner who was cleaning a window on the 25th floor of a skyscraper. He suddenly slips and falls. He has no safety equipment and nothing to soften his fall, but he is not hurt at all. How do you account for that?

Question: If you have 30 white socks, 22 black socks, and 14 blue socks scattered across the floor in the dark, how many would you have to grab to get a matching pair?

Question: There are 100 passengers boarding a 100 passenger airplane. When passenger 1 gets onto the plane, he is dissoriented, so he randomly picks a seat. Each of the remaining passengers (2, 3, 4, etc.) get onto the plane and take their seat if it is available or picks one of the remaining seats at random if it is not.

What is the chance that the last passenger (passenger 100) will get his seat?