Bubba's truck consists of an air resistance of 1110 N when driving at a constant speed of 28.2 m/s. The power generated by his engine to move at constant speed is 42.0 HP. Bubba has his truck now loaded with heavy boxes. The net mass of the truck and cargo is 3190 kg. If his engine is capable to supply 275 horse-powers, then determine the steepest hill which he can climb at a constant speed of 28.2 m/s?