Light sources send out light waves that.

A. travel in one direction.

B. travel at right angles to the source

C. travel every direction except down

D. travel in all directions

A. Travel in one direction

Explanation:

light can be reflected and bent but light originally travels in one direction in straight lines

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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the displacement produced by the body.  

the amount of force subjected to the body.  

the angle between the direction of force and displacement