The gravitational acceleration at any distance r is given by
where G is the gravitational constant, M the Earth's mass and r is the distance measured from the center of the Earth.
The Earth's radius is 
, so the meteoroid is located at a distance of:
And by substituting this value into the previous formula, we can find the value of g at that altitude:
Answer: Tsunami.
Explanation :
Tsunami is the result of a sudden vertical offset in the ocean floor and is most often the result of plate movement on the ocean floor.
Tsunami is caused due to the displacement of a large volume of water like in an ocean. It consists of a series of waves. It destroys coastlines and coastal settlements. It is also known as a tidal wave.
So, the correct option is (b) Tsunami.
Moving
.................................................
C. Maintain correct Posture
I believe your answer should be C. Speed.
