Good Riddles

Question: You want to go to a club but to get in you must respond correctly to what the bouncer says. The bouncer says 12 to one man and the man responds 6, he is allowed in. The bouncer says 6 to another man and the man says 3, he too is allowed in. A third man walks up and the bouncer says 10 and the man responds 5, but he is denied entry.

What number should he have said to get in?

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

What am I?

Question: How much dirt is in a hole that has a radius of 33.2 meters and a height of 78.2 meters?

Question: What runs around the house but doesn't move?

Question: What happens when you throw a blue rock into the yellow sea?