An example of a grad-school level question?
Which gravitational pull has the greatest influence on Earth's tides?

An example of a grad-school level question?
A car skids along the road and smoke appears to be coming from under the tires. The heat that produces the smoke is caused by

An example of a grad-school level question?
A squid is an animal that lives in the ocean. It pumps a stream of water out of its body, causing it to move rapidly. Which of the following mechanical systems moves in a way most similar to the squid?

An example of a grad-school level question?
Kate sees a full moon. About how much time will go by before the next full moon?