$13\mathrm{.}17$ For the cell $(13\mathrm{.}32),$ emfs at $60C$ and $1$ bar $H_2$ pressure as a function of $HCl$ molality $m$ are:

$\backslash$table$[[\frac{m}{molk{g}^{-1}},0\mathrm{.}001,0\mathrm{.}002,0\mathrm{.}005,0\mathrm{.}1],[\frac{E}{V},0\mathrm{.}5951,0\mathrm{.}5561,0\mathrm{.}5050,0\mathrm{.}3426]]$

$($a$)$ Use a graphical method to find $E$ at $60C.($b$)$ Calculate the $60CHCl(aq)$ mean ionic activity coefficients at $m=0\mathrm{.}005mo\frac{l}{k}g$ and $0\mathrm{.}1mo\frac{l}{k}g.$