Well, start by finding his velocity when he hits the mattresses:
V^2 = 0^2 + 2(9.8)(26)
V^2 = 509.6
V ~ 22.57
Now calculate his rate of decceleration from 22.57 m/s to 0 m/s in .95 m:
0^2 = 22.57^2 + 2(a)(.95)
-509.6 = 1.9a
a ~ -268.21 m/s/s
Now apply Newton's first law given his...