$p_2=\frac{p_2}{p_{0\mathrm{.}2}}\frac{p_{0,2}}{p_{0\mathrm{.}1}}\frac{p_{0,1}}{p_1}{p}_1=\frac{1}{7\mathrm{.}824}*1*3\mathrm{.}671*1$atm$=0\mathrm{.}469$atm

$T_2=\frac{T_2}{T_{0\mathrm{.}2}}\frac{T_{0,2}}{T_{0\mathrm{.}1}}\frac{T_{0,1}}{T_1}{p}_1=\frac{1}{1\mathrm{.}8}*1*1\mathrm{.}45*288K=232K$

$p_{0,2}=p_{0\mathrm{.}1}=\frac{p_{0,1}}{p_1}{p}_1=3\mathrm{.}671*1$atm$=3\mathrm{.}671$atm

$T_{0,2}=T_{0\mathrm{.}1}=\frac{T_{0,1}}{T_1}{T}_1=1\mathrm{.}45*288K=417\mathrm{.}6K$ Can someone explain these equations to me please? what is the general equation that is used here? thanks