At a winter recreation resort, snow tubers at the bottom of the hill hook their tubes to a tow rope. a motor pulls the rope so that tubers move at constant velocity to the top of the hill. (ignore the momentary acceleration of the tuber when he first attaches his tube to the rope.) the coefficient of kinetic friction between the tube and the snow is

the answer is a. at the equator

the answer is 3.1 his answer is wrong mines is right

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