A blimp of mass 110 kg is pulled at an angle of 52 degrees downwards with respect to the horizontal for D=7 km on level ground at a constant velocity v=14 m/s. If the coefficient of drag (K in F=Kv^2) is 0.5 kg/m, how much work is done by the person pulling? I know how to find work with the (1/2)mv^2 formula and the Fdcos(angle) formula. But I don't know how to apply the drag into either equation. Do I just solve for F in the coefficient of drag equation then apply it? Or are there more steps?