In 1900, a German physicist discovered an equation that matched experimental data about the emission of light by a hot surface. * a. Max Planck
b. Sir Isaac Newton
c. James Clerk Maxwell
d. Christian Huygens

hey , the answer is c

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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