What Am I Riddles

Question: I am shorter when I stand and taller when I sit.
Sometimes I'm even called a pit.

What am I?

Question: If a man carried my burden, he'd break his back.
I am not rich, but I always leave silver in my track.

What am I?

Question:

Sad, sick, or sloppy I'll help you out,
Use me right and I'll cover your snout.

What am I?

Question: People pick me, and watch me until they give me power. Then they don't stare in my eyes. What am I?

Question: I am pain, I am fear, I will take what you hold dear, Nations shudder when I'm near, Many die when I'm here. What am I?