A) a field
B) the atmosphere
C) a material medium
D) heat

A) artificial lights
B) the energy of distant stars
C) a vacuum
D) the high energy of the Sun

A) speed of EM waves in a vacuum
B) motion of a medium caused by EM waves
C) conversion of EM waves into kinetic energy
D) energy that moves as EM waves

A) always remains constant
B) depends on the source of the waves
C) decreases as the waves spread out
D) increases as the amount of energy increases

A) are refracted
B) are reflected in many directions
C) convert electromagnetic energy into heat
D) pass through the water without interacting with it

A) ultraviolet light
B) x-rays
C) radio waves
D) microwaves

A) ultraviolet light
B) gamma rays
C) x-rays
D) radio waves

A) microwaves
B) x-rays
C) ultraviolet light
D) radio waves

A) infrared light
B) radio waves
C) microwaves
D) ultraviolet light

A) visible light
B) radio waves
C) ultraviolet light
D) microwaves

A) microwaves
B) x-rays
C) ultraviolet light
D) radio waves

A) x-rays
B) ultraviolet light
C) radio waves
D) microwaves