Asonar system measures distance by determining the takes for sound waves to bounce off a surface.

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Explanation:

The sonar is constantly sending signals into the space surrounding him, then he measures the waves that come back by bouncing in surfaces and it calculates the distance that it took those waves to come back to see how far away the surface located is.

supercell thunderstorms are perhaps the most violent of all thunderstorm types, and are capable of producing damaging winds, large hail, and weak-to-violent tornadoes