What is the total work done in the given $P-V$ graph?

In the diagrams $(i)$ to $(iv)$,the variation of volume with changing pressure is shown. $A$ gas is taken along the path $ABCD$. The change in internal energy of the gas will be:

The portion $AB$ of the indicator diagram representing the state of matter denotes:

One mole of an ideal gas in initial state $A$ undergoes a cyclic process $ABCA$,as shown in the figure. Its pressure at $A$ is $P_0$. Choose the correct option$(s)$ from the following:
$(A)$ Internal energies at $A$ and $B$ are the same
$(B)$ Work done by the gas in process $AB$ is $P_0 V_0 \ln 4$
$(C)$ Pressure at $C$ is $\frac{P_0}{4}$
$(D)$ Temperature at $C$ is $\frac{T_0}{4}$

During the thermodynamic process shown in the figure for an ideal gas:

$A$ system goes from $P$ to $Q$ by two different paths in the $P-V$ diagram as shown in the figure. Heat given to the system in path $1$ is $1000 \, J$. The work done by the system along path $1$ is more than path $2$ by $100 \, J$. What is the heat exchanged by the system in path $2$?