Answer:
At sea level, air pressure is greatest because it is caused by the weight of the entire column of atmosphere at that altitude over that location. As altitude increases, the column of atmosphere gets shorter, and so less weight is pressing down at a given altitude, so atmospheric pressure is reduced.
neurotransmitters is the answer
If I can remember correctly, I believe the control is what id being tested...
The green house effect is a natural process that warms the Earth surface.
((Carbon dioxide))
