Considering only $P-V$ work is involved, the total change in enthalpy (in Joule) for the transformation of state in the sequence $X \rightarrow Y \rightarrow Z$ is $\qquad$
[Use the given data: Molar heat capacity of the gas for the given temperature range, $C _{ v , m }=12 J K ^{-1} mol ^{-1}$ and gas constant, $R =8.3 J K ^{-1} mol ^{-1}$ ]
$(i)$ What is $W$ along path $ibf$ ?
$(ii)$ If $W = 13$ cal for path $fi$, what is $Q$ for the path $fi$ ?
$(iii)$ Take $E_{int,i} = 10\,\, cal$ then what is $E_{int,f}$ ?
