Natural gas is very abundant in the united states. compared to other fossil fuels, which describes the waste products of the combustion of natural gas? a) natural gas has no waste products. b) natural gas produces greater amounts of solid waste. c) natural gas produces large quantities of radioactive waste. d) natural gas has no solid waste products, but produce large amount of greenhouse gases.

D) just took the test dont worry

b. lifting dumbbell weight at 20-degree angle from the body after a 45-degree angle

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