A carnot engine whose heat sink is at `27^(@)C` has an efficiency of `40%`. By how many

A carnot engine whose sink is at 290 K has an efficiency of 30%. By how much the temperature of the source be increased to have its efficiency equal to 50%, keeping sink temperature constant

A Carnot engine, whose sink is at 300 K, has an efficiency of 40%. By how much the source temperature should be changed so as to increase the efficiency to 60% ?

An ideal engine whose low-temperature reservoir is at 27^@C has an efficiency of 40%. By how much should the temperature of the high-temperature reservoir be increased so as to increase the efficiency to 50% ?

A Carnot engine whose sinl is at 300K has an efficiency of 40% . By how much should the temperature of source be increased so as to increase its efficiency by 50% of original efficiency.

A Carnot engine whose sink is at 300k has an efficiency of 50%. By how much should the temperature source be increased so as the efficiency becomes 70%?