Question 786742
The general force equation is 


F = ma


F = force
m = mass
a = acceleration


in this case, a = g since g is the acceleration of gravity. The acceleration of gravity is roughly 9.8, so g = 9.8



F = ma


F = mg


W = mg ... (W is the weight, not mass, of this person...the 'weight' is the force of gravity pulling down)


W = 71*9.8


W = 695.8



So the force of gravity is pulling this person down with a force of 695.8 newtons or just 695.8 N.


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So you have a force of 695.8 N pulling the person down and a force of 78 N pulling the person up. Therefore, the net force is 695.8 N - 78 N = 617.8 N and the direction of this force is down