Which of the following statements is true?
a. you are exposed to nuclear radiation every day.
b. most of the nuclear radiation you are exposed to in the environment is man-made.
c. naturally occurring nuclear radiation is called background decay.
d. all natural radiation is at a level low enough to be safe.

Explain in physical terms how a microwave oven works. what would happen when you put a conductor in the microwave oven? explain.

All the simple machines make work easier to do by changing the or of a force. a. size; type b. work; type c. size; direction d. type; direction

The speed of sound in ice, water, and steam is shown. what best explains the speed of sound in different states of matter? sound travels fastest in ice because energy is easier to transfer when the molecules are close together. sound travels slowest in steam because the sound has to move around the gas molecules that are far apart. sound travels fastest in ice because the temperature of solids is always greater, so the heat transfers the sound energy. sound travels slowest in steam because the pressure is so great the sound cannot travel though the steam particles.