The PV diagram below $($Figure $2)$ shows two possible states of a system containing $1\mathrm{.}55$ moles of a monoatomic ideal gas. $(P_1=455\frac{N}{m^2}{V}_1=2\mathrm{.}00m^3,V_2=8\mathrm{.}00m^3)$

a$.$ Draw the process which depicts an isobaric expansion from state $1$ to state $2$ and label this process A $.$

b$.$ Find the work done by the gas and the change in the internal energy of the gas in process A$.$

c$.$ Draw the two$-$step process which depicts an isothermal expansion from state $1$ to the volume $V_2$ followed by an isovolumetric increase in temperature to state $2,$ and label this process $B.$

d$.$ Find the change in internal energy of the gas for the two$-$step process B$.$