Question

which of the following forces act externally on the person - parachute system? choose all answers that apply: a downward force from the person

Explanation:

Step1: Analyze the system

The person - parachute system is considered. Internal forces are those that act between components of the system, and external forces act from outside the system.

Step2: Evaluate Option A

The downward force from the person: The person is part of the person - parachute system. So the force exerted by the person on the parachute (or vice - versa) is an internal force, not an external force. So this option is incorrect.
(Note: Since the full set of options is not provided, but based on the given option A, we can analyze it. Usually, for a person - parachute system, external forces would include gravity (acting downwards on the system from the Earth, an external object) and air resistance (acting on the parachute from the air, which is outside the system). But for the given option A, we can conclude it is not an external force.)

Answer:

Option A (downward force from the person) is not an external force on the person - parachute system. (If other options were provided, we would analyze them similarly. But based on the given option, we state that A is incorrect for being an external force.)