Question

as the altitude increases, how do the weight and mass of the body vary

Answer 1

Thank you for asking the question!
As you move towards the higher altitude your weight changes but the mass remains the same. This happens because the gravitational pull varies subtly as you move around the surface of the Earth, as the altitude and topology also varies. So generally due to this reason weight is lower as we move to the mountains as compared to when we standing at the sea level.
Hope it helps.

Answer 2

Answer : Weight of the object changes with the altitude but the mass remains the same.