Two lbs of water vapor in a piston-cylinder assembly expands at a constant pressure of 250 lbf/in^2 from a saturated liquid vapor mixture of quality x = 0.7 to a volume of 6.88 ft^3. determine the initial and final temperatures, in °f, and the work for the process, in btu.

An ideal otto cycle with air as the working fluid has a compression ratio of 8. the minimum and maximum temperatures in the cycle are 300 k and 1340 k. use constant specific heats at room temperature to determine (a) the amount of heat transferred to the air during the heat- addition kj/kg, (b) the thermal efficiency, and (c) the thermal efficiency of a carnot cycle ope limits. process, in rating between the same temperature