Which is an example of potential energy? a. a swimmer kicking their legs b. a car driving on the road c. an arrow flying at a target d. a yo-yo in someone’s hand

A yo-yo in someones hand

3.2x10^7

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me