Estimate the effective drag coefficient and save it as the variable c_d_effective. Some of the code you need is supplied for you here, but some is not. Refer to the parameter estimation worksheet we did in class for ideas! prob = ODEProblem(spring_mass_simplified, [x => 0.25, y => 1.0, vx => 1.0, vy => 0.0, c_d=>0.1], (0.0,10.0), ) begin function model_f(cd_guess) prob2 = remake(prob, p = [c_d => cd_guess]) sol = solve(prob2, Tsit5(), saveat=0.2) return hcat(sol[x], sol[y]) end end