Which of the following graphs between pressure $(P)$ and volume $(V)$ of a gas correctly shows an isochoric process in thermodynamics?

Two kg of water is converted into steam by boiling at atmospheric pressure. The volume changes from $2 \times 10^{-3} \ m^3$ to $3.34 \ m^3$. The work done by the system is about ....... $kJ$.

The ratio of work done by an ideal rigid diatomic gas to the heat supplied to the gas in an isobaric process is (in $/7$)

$A$ monoatomic gas does $100 J$ of work when it is expanded isobarically. How much heat is given to the gas in the process (in $J$)?

$A$ diatomic ideal gas undergoes a thermodynamic change according to the $P-V$ diagram shown in the figure. The heat given to the gas in process $AB$ is: (in $, P_0 V_0$)

When heat is supplied to a monoatomic gas,it expands at constant pressure. What fraction of the heat supplied is converted into work?