Running on a treadmill is slightly easier than running outside because there is no drag force to work against. Suppose a 60 kg runner completes a 5.0 km race in 18 minutes. Assume the density of air is 1.20 kg/m^3.

A.) Determine the drag force on the runner during the race. Suppose that the cross section area of the runner is 0.72 m^2.

B.) What is this force as a fraction of the runner's weight?