An example of a grad-school level question?
Where will a sidewalk feel hottest on a warm, clear day?

An example of a grad-school level question?
Millions of people living all over the world have cancer. Is cancer a pandemic?

An example of a grad-school level question?
What do the energy resources uranium and coal have in common?

An example of a grad-school level question?

As a sample of mercury changes state from liquid to solid, the atoms of the sample