Stomata open and close in response to- A. water being pumped in and out of guard cells.
B. crystal formation in the plant due to excess glucose.
C. lack of available sunlight during the night.
D. stimulation by auxins producing rapid growth

Dr. arenas is a scientist who has been trying to determine if increasing pressure will increase the sound that occurs when two chemicals explode. it measures the volume of the sound that occurs at the minimum pressure at which the explosion will occur. it then increases the pressure and measures the volume of the explosions that occur. what kind of investigation is the scientist conducting?