HELP PLEASE The planet Mars, our moon, and Halley's comet all

A) reflect the sun's light.
B) are older than the earth.
C) have highly elliptical orbits.
D) were formed from collisions with the earth.

What type of electromagnetic wave is used in security pens? a. x-rays c. microwaves b. visible light d. ultraviolet radiation select the best answer from the choices provided

Which safety measures should you follow during a thunderstorm? check all that apply. (a) avoid touching anything that conducts electricity. (b) avoid touching a person who has been struck by lightning. (c) go outside. (d) keep your computer turned off. (e) stay out of water. (f) stay inside.

Which of the following is not a transverse wave? a) soundb) lightc) radiod) all of thesee) none of these