A $P-T$ graph is shown for a cyclic process. Select correct statement regarding this

Two moles of helium gas are taken over the cycle $ABCDA$, as shown in the $P-T$ diagram. Assuming the gas to be ideal the work done on the gas in taking it from $A $ to $B$ is …… $R$

For one complete cycle of a thermodynamic processes on a gas as shown in $P-V$ diagram. Which is true

In a certain thermodynamical process, the pressure of a gas depends on its volume as $kV ^{3}$. The work done when the temperature changes from $100^{\circ} C$ to $300^{\circ} C$ will be ………. $nR$, where $n$ denotes number of moles of a gas.

A gas is taken through the cycle $A\to B\to C\to A$ as shown. What is the net work done by the gas …… $J$ $?$