Score: 2 Points

Suppose, in your nightmare, you have been thrown to a cylinder-shaped hole which is as long as the diameter of the earth and goes through the center of the Earth. If this nightmare occurs, in reality, you will oscillate at a certain frequency about the center of the Earth.

What is the period of this oscillation?
Your answer should be in second. Don't insert the unit.
Assume that,

Image source: Fall through the earth


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First Solve @jaber