A four-stroke gasoline engine with a compression ratio of 10 is modeled using an ideal air-standard Otto cycle consisting of the following four internally reversible processes. Process 1-2: Adiabatic compression from absolute pressure of 1 bar and temperature of 300 K (State 1) Process 2-3: Constant volume energy addition by heat transfer to a temperature of 2000 K (State 3) Process 3-4: Adiabatic expansion Process 4-1: Constant volume energy rejection by heat transfer Consider variable properties for air. Molecular weight of air = 28.97 kg/kmol. (a) Find the pressure and temperature at all states in the cycle, in bar and K, respectively. (b) Determine the thermal efficiency of the cycle, in %. (c) Calculate the mean effective pressure for the cycle, in bar. (d) Find the total specific entropy generation for the energy rejection process, in kJ/kg-K. Assume a surrounding temperature of 20C. (e) Show the cycle on P-v and T-s diagrams and the appropriate lines of constant temperature and lines of constant pressure for the four states. Label states and identify process directions with arrows.