1: The greatest ocean depth at which life exists is:

A. 1,000 ft.

B. 2,500 ft.

C. 20,000 ft.

D. 35,800 ft.

2: What percentage of Earth's surface is covered by water?

A. 30%

B. 50%

C. 70%

D. 92%

3: The most deadly risk divers face underwater is:

A. Sharks

B. Anxiety and Panic

C. Malfunctioning equipment

D. Hypothermia

4: In what way is water at the surface different from water at great depth?

A. Temperature

B. Pressure

C. Visibility

D. All of the above

5: The air we breathe is made up of what percentage oxygen?

A. 100%

B. 79%

C. 21%

D. 12%