A gas within a piston-cylinder assembly executes a Carnot power cycle during which the isothermal expansion occurs at TH = 600 K and the isothermal compressions occurs at TC = 300 K. Determine:
a) The thermal efficiency
b) The percent change in thermal efficiency if TH increases by 15% while TC remains the same
c) The percent change in thermal efficiency if TC decreases by 15% while TH remains the same
d) The percent change in thermal efficiency if TH increases by 15% and TC decreases by 15%.