If we shake the branches of tree, the fruits fall why
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becauae of the gravity

Explanation:

Gravity is the force by which a planet or other body draws objects toward its center. The force of gravity keeps all of the planets in orbit around the sun.

They proposed that gravity is actually made of quantum particles, which they called "gravitons." Anywhere there is gravity, there would be gravitons: on earth, in solar systems, and most importantly in the miniscule infant universe where quantum fluctuations of gravitons sprung up, bending pockets of this tiny space

1 - wave length

2 - amplitude

3 - crest

4 - trough

explanation:

duh.

the force on the thing and the distance the force moves the thing