Support an argument that the gravitational force exerted by Earth on objects is directed down.

Astronauts have safety tethers which are the same thing as cords/ropes which prevents them from floating away from the moon.

If you jump up and down on Earth, what happens? You go right back down. If the gravitational force wasn't going down, we wouldn't even be able to stand on Earth without floating away.

option c is the correct answer.

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what do the different brain waves do?

explanation:

brainwaves are produced by synchronised electrical pulses from masses of neurons communicating with each other. brainwaves are detected using sensors placed on the scalp. brainwave speed is measured in hertz (cycles per second) and they are divided into bands delineating slow, moderate, and fast waves.