The above figure provides steady$-$state data for a throttling valve in series with a heat exchanger. Saturated liquid Refrigerant $134$a enters the valve at a pressure of $9$ bar and is throttled to a pressure of $2$ bar. The refrigerant then enters the heat exchanger, exiting at a temperature of $10$C with no significant decrease in pressure. In a separate stream, liquid water at $1$ bar enters the heat exchanger at a temperature of $25$C with a mass flow rate of $2$ kg$/$s and exits at $1$ bar as liquid at a temperature of $15$C$.$ Stray heat transfer and kinetic and potential energy effects can be ignored. Determine: a$)$ the temperature, in $$C$,$ of the refrigerant at the exit of the valve. b$)$ the mass flow rate of the refrigerant, in kg$/$s$.$