Fgravity = m*g
Ffriction = k*A*v^2
Ftotal = Fgravity - Ffriction
a = Ftotal/m
v = v+a*dt
if t<7 then Fgravity>Ffriction
if 7<t<67 then v =55,88 (meters per second)
if t>67 then A = 45 (square meter)
if t>67 then Fgravity<Ffriction
the t defines the seconds the first 7 seconds are the free fall...