If a Carnot engine works between $127^{\circ} C$ and $527^{\circ} C$,then its efficiency is ...... $\%$

In a Carnot engine,the absolute temperature of the source is $25 \%$ more than the absolute temperature of the sink. The efficiency of the engine is (in $\%$)

$A$ Carnot's heat engine works between the temperatures $427^{\circ} C$ and $27^{\circ} C$. How much heat in $kcal/s$ should it consume per second to deliver mechanical work at the rate of $1.0\,kW$?

$A$ Carnot engine takes $300$ calories of heat from a source at $500 \,K$ and rejects $150$ calories of heat to the sink. The temperature of the sink is (in $\,K$)

$A$ Carnot engine has an efficiency of $\frac{1}{6}$. When the temperature of the sink is lowered by $57 \ K$,its efficiency becomes $\frac{1}{3}$. The temperature of the source is: (in $K$)

The efficiency of a Carnot engine depends on what,and of what is it independent?