What happens to sound waves then the source of a sound is moving toward you?

Write the chemical symbols for three different atoms or atomic cations with 27 electrons. asap!

One way that radioactive waste is treated is by burying it in repositories. the repositories are found only in states with very low populations. true or false? a. trueb. false(also i meant to put high school but it put down middle school instead)

Earth's axis of rotation is tilted at an angle of 23.5 degrees. what is one change you would see on earth if its axis was not tilted?