A person sits on a stool in science class. They weigh 145 pounds. What force does the stool excerpt on the person to prevent them from crushing the stool?

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

0.93xc=0.93x3x10^8m/s

2.54cm is 1 inch

360seconds i 1 hr