If this motorcycle started at rest at t=0, what velocity would it have after 4 seconds? a 2 m/s

b 8 m/s

c 0 m/s

d 4 m/s

then it would be fast

Explanation:

B 8 m/s

Explanation:

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

i would say