Good Riddles

Question: Paul is 20 years old in 1980, but only 15 years old in 1985.How is this possible?

Question: The first is a sign of something good,
the second says whereto;
the third is vulgar and mean,
the fourth is bound by a ring;
the fifth is the noble one.
Together they all drum.

What are they?

Question: I'm round at the ends and high in the middle.What am I?

Question: Walk on the living, they don't even mumble.
But walk on the dead, they mutter and grumble.

What are they?

Question: You use me from your head to your toes,
the more I work the thinner I grow.

What am I?