Which of the following statements best explains why the table of known elements is called the "periodic table"? a. the table is used mostly by molecular researchers who use it infrequently to organize their lab chemicals. b. the table organizes the elements alphabetically so that the elements are easy to find. c. the table organizes the elements according to regular, repeating chemical properties. d. each element on the table is referred to as a "period".

C. The table organizes the elements according to regular, repeating chemical properties. I hope that helps :)

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