The number we need in order to answer the question belongs in the space between the words "is" and "of". You left that blank blank, so there really isn't any question here to answer.
HOWEVER ... the refractive index of a medium can never be less than 1.0 , so we know for sure that <em>choice-a can't be</em> the correct answer.
Transverse waves are always characterized by particle motion being perpendicular to wave motion. A longitudinal wave is a wave in which particles of the medium move in a direction parallel to the direction that the wave moves.
Run inside if you are outdoors
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Answer:

Explanation:
We can use the conservation of momentum. The initial momentum is equal to the final momentum:
x-coordinate

(1)
y-coordinate

(2)
We can divide equations (2) and (1):



I hope it helps you!