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

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

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

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

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

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

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

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

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

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

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

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