I'm not sure, I think it's option A.
Let me know if I'm wrong!
I haven't worked on Part-A, and I don't happen to know the magnitude of the gravitational force that the Sun exerts on the Earth.
But whatever it is, it's exactly, precisely, identical, the same, and equal to the magnitude of the gravitational force that the Earth exerts on the Sun.
I think that's the THIRD choice here, but I'm not sure of that either.
Its physical weathering and physical weathering can be sometimes called mechanical weathering it includes the processes which break rocks apart changing their chemical composition.
