physics. please help me!!?

Question

A 65.0 kg diver steps off a diving board and drops straight down into the water. The net force when in the water is an upward 1250 N. If the diver comes to rest 4.0 m below the water's surface, what is the total distance between the diving board and the diver's stopping point underwater?

Answer 1

(65)(9.80665)(h - 4) = (4)(1250)
h - 4 = (4)(1250) / (65)(9.80665)
h = 4(1 + (1250) / (65)(9.80665) )
h ≈ 11.84397 m ≈ 11.8 m