The waves to which we give the name “light” are a narrow band of ().
A. the electromagnetic spectrum
B. radio waves
C. ultra-violet waves
D. infra-red waves
The trichromatic theory proposes that we have ().
A. three kinds of optic nerves
B. a triad of lenses
C. three kinds of cones
D. three kinds of rods
A sound wave ().
A. can travel through outer space
B. cannot travel through water
C. has frequency, but not amplitude
D. requires a medium such as air or water
What structure in the ear is similar in function to the eye's retina? ()
A. The basilar membrane
B. The auditory nerve
C. The tympanic membrane
D. The oval window
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