An example of a grad-school level question?
What is the main source of energy for the water cycle?

An example of a grad-school level question?
In 1918, an outbreak of influenza infected 500,000 people all over the world. Tens of millions of those infected died. In 1994, an outbreak of pneumonic plague spread quickly through the city of Surat in India, killing 52 people. Which statement best describes the two events?

An example of a grad-school level question?
When a book is dropped onto a wooden desk, the molecules in the wood begin to vibrate from the force of the book. Which of these is produced by the vibrations?

An example of a grad-school level question?
What is taken in by the leaves of a tree so it can make its own food?