A Carnot engine takes \( 5000 \ \text{kcal} \) of heat from a reservoir at \( 727^\circ \text{C} \) and gives heat to a sink at \( 127^\circ \text{C} \). The work done by engine is:
\( 3 \times 10^{6} \ \text{J} \)
Zero
\( 12.6 \times 10^{6} \ \text{J} \)
\( 8.4 \times 10^{6} \ \text{J} \)
