$A$ gas in a closed container undergoes the cycle $ABCA$ as shown in the figure. The net heat absorbed by the gas after it has completed $10$ cycles is

The following figure shows a $P-T$ graph for four processes $A, B, C$ and $D$. Select the correct alternative.

The figure shows the $P-V$ plot of an ideal gas taken through a cycle $ABCDA.$ The part $ABC$ is a semicircle and $CDA$ is half of an ellipse. Then,

$A$ cyclic process $ABCD$ is shown below in the given $P-V$ diagram. Which of the following diagrams represents the same process in a $P-T$ diagram?

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 .... $J$.

The $P-V$ diagram shows seven curved paths (connected by vertical paths) that can be followed by a gas. Which two of them should be parts of a closed cycle if the net work done by the gas is to be at its maximum value?