Answer
a) $T=526R$
b) $T=693.81R$
c)$T=700R$
Work Step by Step
a) Based on the ideal gas equation:
$T=\frac{PV}{mR}=\frac{P\upsilon}{R}=\frac{400psia*0.1384\frac{ft^3}{lbm}}{0.10517\frac{psiaft^3}{lbmR}}=526R$
b) Using the generalized comrpessibility chart:
$P_{R}=\frac{P}{P_{cr}}=\frac{400psia}{588.7psia}=0.679$
$\upsilon_{R}=\frac{\upsilon}{\frac{RT_{cr}}{P_{cr}}}=\frac{0.1384\frac{ft^3}{lbm}}{\frac{0.10517\frac{psiaft^3}{lbmR}*673.6R}{588.7psia}}=1.150$
From Fig A-15a
$T_{R}=1.03$
Then $T=T_{R}T_{cr}=1.03*673.6=693.81R$
c)From table A-13E:
$T=240^{\circ}F=700R$
