Answer:
D
Explanation:
pretty sure its D because none of the other answers would make sense, and this is what I've seen in restaurants.
The answer is C. 33 percent
The diaphragm is another term for the aperture, so it controls the amount of light passing into the film camera.
The one vibrating faster if you think about when singing in order to hit high notes you must push air faster while when singing lower you slow down the speed o air being pushed its the same with high pitch Nd low pitch frequency higher equals faster and lower equals slower
