$A$ thermodynamic cycle $xyzx$ is shown on a $V-T$ diagram.
The $P-V$ diagram that best describes this cycle is
(Diagrams are schematic and not to scale)

In the given figure,two processes $A$ and $B$ are shown by which a thermodynamic system goes from an initial state $i$ to a final state $f$. If $\Delta Q_A$ and $\Delta Q_B$ are respectively the heats supplied to the systems,then:

An ideal gas goes from state $A$ to state $B$ via three different processes as indicated in the $P-V$ diagram. If $Q_1, Q_2, Q_3$ indicate the heat absorbed by the gas along the three processes and $\Delta U_1, \Delta U_2, \Delta U_3$ indicate the change in internal energy along the three processes respectively,then

As shown in the figure,the amount of heat absorbed along the path $ABC$ is $90\,J$ and the amount of work done by the system is $30\,J$. If the amount of work done along the path $ADC$ is $20\,J$,the amount of heat absorbed will be .... $J$.

In a thermodynamic process,the pressures and volumes corresponding to some points in the figure are $P_A = 3 \times 10^4 \, Pa$,$V_A = 2 \times 10^{-3} \, m^3$,$P_B = 8 \times 10^4 \, Pa$,and $V_D = 5 \times 10^{-3} \, m^3$. In process $AB$,$600 \, J$ of heat is added,and in process $BC$,$200 \, J$ of heat is added to the system. The change in the internal energy in process $AC$ would be .... $J$.

$A$ system goes from $A$ to $B$ via two processes $I$ and $II$ as shown in the figure. If $\Delta U_I$ and $\Delta U_{II}$ are the changes in internal energies in the processes $I$ and $II$ respectively,then: