Which word means "the remains or imprints of once-living organisms found in layers of rock

"why is graphite used instead of gold or copper wires to conduct electricity in very hot situations such as an industrial kiln? " that's the question, but the thing is, i don't even understand what an "industrial kiln" xd assistance would be < 3

The of a machine determines its "usefulness." a. input force b. output force c. mechanical advantage

What is the measure of a change in an objects velocity?