HW#$5-2$ R$-134$a enters the evaporator coils placed at the back of the freezer section of a household refrigerator at $100$kPa with a quality of $0\mathrm{.}2$ and leaves at $100$kPa and $-266C.$ If the adiabatic compressor consumes $600W$ of power and the COP of the refrigerator is $1\mathrm{.}2,$ determine $($a$)$ the mass flow rate of the refrigerant and $($b$)$ the rate of heat rejected to the kitchen air.