A parachutist of total mass 70 kg is falling vertically through the air at a constant speed of 8 m s . What is the total upward force acting on the parachutist

The parachutist is falling at a constant speed, so the net force acting on them is zero. The only forces acting on the parachutist are their own weight (magnitude w, pointing downward) and the drag produced by the parachute (mag. d, pointing upward). By Newton's second law,

d - w = 0

or d = w. The parachutist's weight is

w = (70 kg) (9.80 m/s²) = 686 N

so that the total upward force is also 686 N.

305.7

explanation:

density =m/v

density =917/3.00

density = 305.

approximately = 305.7

in four significant figures