3. A truck has a drag coefficient based on frontal area of Cp = 0.86. The truck has a mass of 12,750 kg anda frontal area of 10.5 m2. If the truck is traveling at constant speed on a level road, the forces retarding itsforward progress are the drag and the rolling friction. The force due to rolling friction can be written as F_{\mathrm{rf}}=W f_{r}\left(1+\frac{V}{V_{0}}\right) where V is the truck speed in m/s, Vo = 30 m/s and fr (the coefficient of rolling resistance) is approximately0.008 for a truck on concrete or asphalt. Plot the total power the engine must supply as a function of trucks peed, V. Comment on the relative importance of drag and rolling friction in the fuel consumption of the truck.

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