This type of listening response is called back-channel signal. This allows the speaker to know that the listener is attentive or willing to engage a conversation between them. It is shown through short utterances, facial expressions, head nods and others.
Gamma rays, X-rays, most ultraviolet rays, and some infrared are absorbed by the atmosphere but do not reach the Earth's surface
Like a then it would be A something I guess it goes like that
Answer:

Explanation:
distance between ship A and B = 32 mile
Ship A velocity in south, dx/dt = -16 mph
Ship B is sailing toward east with speed, dy/st = 12 mph
time = 1 hour
rate of change of distance between them = ?
x be the distance travel after t time
X = 32 + x
Let distance between them be z
now, using Pythagoras theorem to calculate distance between ships after 1 hours
z² = x² + y²
z² = (32 + x)² + 12²
z² = (32 - 16)² + 12²
z = √400
z = 20 miles
now, calculation of rate of change of distnace
z² = (32 + x)² + y²
differentiating both side w.r.t. time





hence, the rate is the distance between them changing at the end of 1 hour is equal to 