The efficiency of an ideal heat engine working between the freezing point and boiling point of water is ........ $\%$

If a Carnot engine functions at a source temperature of $127^{\circ}C$ and a sink temperature of $87^{\circ}C$,what is its efficiency in $\%$?

$A$ Carnot engine operates between $227^{\circ}C$ and $27^{\circ}C$. The efficiency of the engine will be:

In a heat engine,the temperature of the source and sink are $500\, K$ and $375\, K$. If the engine consumes $25\times10^5\, J$ per cycle,the work done per cycle is

$A$ diatomic ideal gas is used in a Carnot engine as a working substance. If during the adiabatic expansion part of the cycle,the volume of the gas increases from $V$ to $32V$,the efficiency of the engine is:

$A$ Carnot engine,whose efficiency is $40 \%$,takes heat from a source maintained at a temperature of $600 \ K$. If it is desired to have an efficiency of $60 \%$,then the intake temperature for the same exhaust (sink) temperature should be: (in $K$)