What would happen if scientists dis not communicate

The of a machine determines its "usefulness." a. input force b. output force c. mechanical advantage

The solar panels used by mark function because of the photoelectric effect. light shines on the cells causing electrons to be ejected from the metal, which produces an electric current. at night on mars, no light will fall on the solar cells and no electric current will be generated. according to your notes, what type of light is typically needed to cause the photoelectric effect? a)visible b)ultraviolet c)infrared

Erosion of the beach is normally a slow process. however, in certain situations, large chunks of shore may wash out to sea. what could cause this to happen?