An ideal Otto Cycle with air as the working fluid has a compression ratio of10. The minimum temperature and pressure in the cycle are 25 degrees celsius and 100 kPa respectively. The highest temperature in the cycle is 1000 degrees celsius. Using the PG model for air with properties: k =1.4, c_p = 1 kJ.kg.K, c_v = 0.717 kJ/kg.K, determine the exhaust temperature (temperature at the end of the expansion stroke) in Kelvins.