The internal energy (U) of an ideal gas is plotted against volume for a cyclic process ABCDA, as shown in the figure.
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/891585/original_Dia_28.20.png)
The temperature of the gas at B and C are
500 K and
300 K, respectively. The heat absorbed by the gas (in cal/mol) in this cyclic process, is :