How do scientist know about the interior of the earth?

By seismic waves ..

Explanation:

Earthquakes that generated by shock waves and exposing that travel trough the surface of the earth revealed the interior of the earth...

Hope i helped u...

scientists rely on seismic waves—shock waves generated by earthquakes and explosions that travel through Earth and across its surface—to reveal the structure of the interior of the planet.

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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answer would be letter choice (a),   a ball resting on a shelf. would be another example of potential energy   >   stored energy > not moving.

a ball spinning on a finger   >   kinetic energy > moving energy

a ball rolling on the ground   >   kinetic energy   > moving energy

a   ball flying through the air   > kinetic energy   >   moving energy

hope that                                         : )