What Am I Riddles

Question: 100 feet in the air, yet its back is on the ground.

What is it?

Question: To give me to someone I don't belong to is cowardly, but to take me is noble.
I can be a game, but there are no winners.

What am I?

Question: Looking at my face, I'm no more than six.
Look at the rest of me and I'm 21.
You'll see my twin and me in Las Vegas.
Say my name and you'd be uttering a threat.

What am I?

Question: Had by few but treasured by all,
I'm on the inside and outside and I make men fall.

What am I?

Question: What am I?