I attempted-HELP

A 600 N skydiver in free fall is accelerating at -7.6 m/s^2 rather than -9.8 m/s^2 because of the force of air resistance. How much drag force is acting on the skydiver? a)58.2 b)65.3 c)61.4 d)40.2 I use the equation Σ(F)vertical-ma=0 To find m I did: 600...