The effector of a feedback mechanism is usually which part of the body?
a. skin
b. brain
c. gland
d. stomach

significant amounts of nitrogen oxides, carbon monoxide, and other pollution

explanation:

passenger vehicles are a major pollution contributor, producing significant amounts of nitrogen oxides, carbon monoxide, and other pollution. in 2013, transportation contributed more than half of the carbon monoxide and nitrogen oxides, and almost a quarter of the hydrocarbons emitted into our air.

i'd say that the moon rock is about 2.2 billion years old.

b. the carbon cycle ensures living things have a source of hydrogen

c. heat from the poles back down towards the equator.