I need to lnow the solve of these questions

Apossible explanation for a set of facts that can be tested by further investigation is called

This is the number of complete movements of a wave per second.

This is a form of winter precipitation. it is frozen precipitation falling as ice pellets. snowflakes melt into raindrops as they pass through a thin layer of warmer air. the raindrops then refreeze into particles of ice when they fall into a layer of sub-freezing air near the surface of the earth. this precipitation is called a) hail. b) rain. c) sleet. d) snow.