Four identical metal plates are painted either black or white and have either a dull or shiny surface. They are heated to the same temperature.

Which plate radiates thermal energy at the greatest?

A. the plate that is dull and black

B. the plate that is dull and white

C. the plate that is shiny and black

D. the plate that is shiny and white

the second one and the forth one are in the purple because they are opinions and the rest are in the yellow

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