A person of mass 81.7 kg escapes from a burning

building by jumping from a window situated
28.9 m above a catching net.
The acceleration of gravity is 9.8 m/s^2
.
If air resistance exerts a force of 123.1 N
on him as he falls, determine his speed just
before he hits the net.
Answer in units of m/s.

im with all of you on this mass stuff my teacher isn't helping just confusing me and I get almost all a's in my classes