Answer:
Used to keep prisoners silent and to make temporary repairs on cars.
I go around in circles, But always straight ahead Never complain, No matter where I am led.
Angels and pilots earn these.
What time is spelled the same forwards and backwards?
Even if you throw it away, it still comes back.
I am the fountain from which no one can drink. For many I am considered a necessary link. Like gold to all I am sought for, but my continued death brings wealth for all to want more.