$1.(20$ points, $5$ points each$)$ Determine whether each of the following processes are irreversible, reversible, or impossible. Show your work, calculations, and table values to justify your answer. HINT: Do not rely on the calculations alone since there may be some roundoff error; use your best judgment if a process appears reversible.

$($a$)$ An R$-134$a mixture $(\backslash (0\mathrm{.}5\backslash$mathrm$\{$~kg$\},20\backslash \%\backslash )$ quality$)$ at $200$ kPa is heated until it becomes a saturated vapor. Take the refrigerant temperature as the boundary temperature.

$($b$)$ R$-134$a $(\backslash (0\mathrm{.}7\backslash$mathrm$\{$~kg$\}/\backslash$mathrm$\{$s$\})\backslash )$ at $500$ kPa and $\backslash (40^\{\backslash$circ$\}\backslash$mathrm$\{$C$\}\backslash )$ is sent through a condenser at constant pressure until it becomes a saturated liquid. Take $\backslash (25^\{\backslash$circ$\}\backslash$mathrm$\{$C$\}\backslash )$ as the boundary temperature.

$($c$)$ Saturated water vapor $\backslash ((1\backslash$mathrm$\{$~kg$\}/\backslash$mathrm$\{$s$\})\backslash )$ at $100$ kPa is sent through a compressor adiabatically to $2$ MPa and $\backslash (400^\{\backslash$circ$\}\backslash$mathrm$\{$C$\}\backslash ).$

$($d$)$ Water vapor $(0\mathrm{.}5$ kg $)$ initially at $\backslash (600^\{\backslash$circ$\}\backslash$mathrm$\{$C$\}\backslash )$ and $5$ MPa is expanded in a container adiabatically to a saturated vapor at $100$ kPa $.$