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as the skydiver falls to earth, she experiences positive acceleration due to
gravity
inertia.
friction
air resistance

As the skydiver falls to the Earth, she experiences positive acceleration only due to gravity.

Explanation:

As the skydiver falls to the Earth, she experiences friction in the form of air resistance which tries to slow her down and is proportional to the her velocity. So it cannot have a positive acceleration as it acts in opposite direction to slow her down.

Inertia during skydiving is experienced when we open an parachute, the parachute slows down the speed of are descent hence changing our inertia of motion with a velocity.

Only the Earth's, gravitational field has an positive acceleration as it pulls us towards the Earth, hence increasing our velocity.

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