PROBLEM $4$:

$[30$ Points$]$

A $0\mathrm{.}1-m^3$ rigid tank contains saturated refrigerant$-134$a at $800$ kPa $.$ Initially, $30\%$ of the volume is occupied by liquid and the rest is occupied by vapor. A valve at the bottom of the tank is opened, and liquid is withdrawn from the tank. Heat is transferred to the refrigerant from a source at $60C$ so that the pressure inside the tank remains constant during the process. The valve is closed just when there is no liquid left in the tank. Determine:

a$)$ the mass discharged from the tank, in kg$.$

$(10$ points$)$

b$)$ the heat transferred, in kJ $.$

$(10$ points$)$

c$)$ the entropy generated during the process, in $k\frac{J}{K}.$

$(10$ points$)$