Good Riddles

Question: Feathers, I am as light,
But quite heavy if squeezed tight.
I'm seen as clean and pure,
but often talked about with dirty terms.
What am I?

Question: John put a coin in a bottle and put a cork on the bottle and later managed to get the coin out without taking out the cork or breaking the bottle. How did he do it?

Question: My name can have any letter of the alphabet, but I always have 2 X's.

What am I?

Question: I drape the hills in white,
I do not swallow, but I do bite.

What am I?

Question: Five pirates are parting ways after finding a treasure of 100 pieces of gold. The pirates decide to split it based on a vote. Each pirate, from oldest to youngest, gets to propose a plan on how to split the gold.

If at least 50 percent of the other remaining pirates agree on the plan, that is how they will split the gold. If less than 50 percent of the pirates agree, the pirate who came up with the plan will be thrown overboard. Each pirate is smart, greedy, and wants to throw as many others overboard as possible without reducing the amount of gold they get.

What plan can the first (oldest) pirate propose to live and get as much gold as possible?