The force between two massive objects is f. If the distance between the two objects is tripled, the new gravitational force between both objects is f/9 f f/3 3.

Abecause its more effective

Nucleus for question ome

Answerigneous bedrock of the oceanic crust;

Ke reqd to move from 0 to 50 will be proportional to 50x50 or 2500. this is equal to w.  to change vel from 50 to 150 you need energy prop to 22500 - 2500 = 20,000. this corresponds to 8w.  best answer is a) . work reqd is prop to velocity squared.