A 2500-lb car (CD = 0.35, Af = 25 ft^2, and ? = 0.002378 slugs/ft^3) has 14-inch-radius wheels, a drivetrain efficiency of 90%, an overall gear reduction ratio of 3.2 to 1, and drive axle slippage of 3.5%. The engine develops a maximum torque of 200 ft-lb at 3500 rev/min. What is the maximum grade this vehicle could ascend, on a paved surface, while the engine is developing maximum torque? (Assume that the available tractive effort is the engine-generated tractive effort.)
Step by step/required formula explanation needed