Which statement about dormant volcanoes must be true?
athey can never erupt again. incorrect answer
bthey have not erupted for a very long time. incorrect answer
cthey will erupt within the next 12 months. incorrect answer
dthey were formerly stratovolcanoes.

They have not erupted for a long time

Explanation:

They have not erupted for a long time is correct because dormant volcanoes are volcanoes that are active and have erupted once in the last 10,000 years. Because they are active, they will erupt again in the future.

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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