An example of a grad-school level question?
Which technology used to generate electrical power involves a trade-off between economical electricity and long-term waste disposal problems?

An example of a grad-school level question?
Which of these is the main function of a cell wall?

An example of a grad-school level question?
A metal ball has a constant velocity of zero. Which other quantity must also be zero?

An example of a grad-school level question?
Which unit is used to indicate the amount of energy in food?