16. Where is the tropical zone? a. near the poles
b. between the polar and temperate zones
c. surrounding the equator
d. near Earth's axis

I believe it is C.

Explanation:

This is because this is where it is hottest and where a lot of the tropics are located.

what statement best describes the difference between the sympathetic and parasympathetic nervous systems?

the sympathetic nervous system prepares the body for intense physical activity and is often referred to as the fight-or-flight response. the parasympathetic nervous system has almost the exact opposite effect and relaxes the body and inhibits or slows many high energy functions.