Is $P\Delta V$ an extensive or intensive variable?

In changing the state of a thermodynamic system from state $A$ to state $B$, the heat supplied to the system is $Q$ and the work done by the system is $W$. The change in its internal energy is

The increase in internal energy of $2$ moles of gas when its temperature is raised from $340 \ K$ to $342 \ K$ is ........ $cal$. Given $C_v = 4.96 \ cal/mole \ K$.

In a given process,for an ideal gas,$\Delta W = 0$ and $\Delta Q < 0$. Then,for the gas,

$A$ gas is taken from state $A$ to state $B$ along two different paths $1$ and $2$. The heat absorbed and work done by the system along these two paths are $Q_1, Q_2$ and $W_1, W_2$ respectively. Then:

Heat given to a system is $35 \ J$ and work done by the system is $15 \ J$. The change in the internal energy of the system will be ..... $J$.