Air pressure is caused by the air molecules around us. Air particles are always in random and continuos motion, bombarding each other in random direction. As air particles collide they create pressure.
Answer:
A. an increase in the greenhouse effect
Explanation:
Carbon dioxide controls the amount of water vapor in the atmosphere and thus the size of the greenhouse effect.
Answer:
Moving things in and out of the cell is an important role of the plasma membrane. It controls everything that enters and leaves the cell. There are two basic ways that substances can cross the plasma membrane: passive transport, which requires no energy; and active transport, which requires energy.
A, because it the constant variable
The magnetic field of a bar magnet is the strongest at either pole of the magnet. It is equally strong at the North Pole when compared with the south pole. So I would say the answer is A.
