2.3 An electric vehicle has the following parameter values: m = 692 kg. C₂ = 0.2, A, = 2 m². C₁ = 0.009, and C, = 1.75 10 s²/m² Also, take =1.16 kg/m³ and g=9.81 m/s². (a) EV at rest-The EV is stopped at a stop sign at a point in the road where the grade is +15%. The tractive force of the vehicle is supplied by the vehicle brakes. (i) Calculate the tractive force necessary for zero rolling resistance. (The vehicle is at rest.) (ii) Calculate the minimum tractive force required from the brakes to keep the EV from rolling down the grade. (b) EV at constant velocity-The EV is moving at a constant velocity along a road that has a constant grade of -12%. (i) Plot, on the same graph, the magnitudes of the tangential gravitational force (FgxT), the aerodynamic drag force (FAD), and the rolling resistance force (Froll) versus velocity for 0<V= 180 mph. Over that range of velocity, does Ferdominate? When does FAD dominate? When does Froll dominate? Label these regions on the graph. (ii) Derive an expression for the tractive force as a function of velocity. Plot this expression on its own graph. Is the tractive force always in the same direction?