Describe the oceans and explain how the water cycle affects the salinity of the ocean

Well the ocean is... uh, salty! Alright all joking aside, the ocean is largest body of water in world, in fact it covers 3/4 of the entire world, but since it contains so much salt we can't drink it. Now the water cycle allows us to drink it, and here's how! The Sun evaporates the surface layer of the oceans, not a lot though, now since salt is a solid it can't be evaporated, this increases the salinity of the oceans. Now let's say a strong wind pushes the evaporated water (or water vapor) onto land. Next the water molecules bind together forming clouds. When the clouds get so heavy with water, they must release some of that unneeded water. They do it through rain. Then some of the rain rolls off of land and back into the oceans decreasing the salinity. This is known as run off. 
i hope this answers your question!

The magnitude of the free-fall acceleration at the orbit of the Moon is (, where ).

Explanation:

According to the Newton's Law of Gravitation, free fall acceleration (), in meters per square second, is directly proportional to the mass of the Earth (), in kilograms, and inversely proportional to the distance from the center of the Earth (), in meters:

(1)

Where:

- Gravitational constant, in cubic meters per kilogram-square second.

- Mass of the Earth, in kilograms.

- Distance from the center of the Earth, in meters.

If we know that , and , then the free-fall acceleration at the orbit of the Moon is: