Amirror faces a cliff located some distance away. mounted on the cliff is a second mirror, directly opposite the first mirror and facing toward it. a gun is fired very close to the first mirror. the speed of sound is 336 m/s. how many times does the flash of the gunshot travel the round-trip distance between the mirrors before the echo of the gunshot is heard?

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 answer is a. the yacht traveled from the dock north to the 200-meter marker in the bay in less than 5 minutes, giving the passengers several more hours to fish.

im doing peak rn so sry if its wrong