Problem $11-60$: two$-$evaporator compression refrigeration system

A two$-$evaporator compression refrigeration system as shown in Figure uses refrigerant$-134$a as the working fluid. The system operates evaporator $1$ at $0C,$ evaporator $2$ at $-26\mathrm{.}4C,$ and the condenser at $800$ kPa $.$ The refrigerant is circulated through the compressor at a rate of $0\mathrm{.}1k\frac{g}{s}$ and the low$-$temperature evaporator serves a cooling load of $8$ kW $.$ The refrigerant is saturated liquid at the exit of the condenser and saturated vapor at the exit of each evaporator, and the compressor is isentropic$.$

Determine the cooling rate of the hightemperature evaporator, the power required by the compressor, and the COP of the system.

Answers: $6\mathrm{.}58kW,4\mathrm{.}51kW,3\mathrm{.}24$

$($Please solve the quastion by your hand $,$ and using P$-$h digram $)$