If the radio waves that are sent from the speed gun have a frequency of 400,000,002 Hz and the radio waves reflected off an approaching car have a frequency of 400,000,109 Hz, what is the speed of the car? (Hz is the SI unit of frequency, equal to cycles per second).

Arefrigerator uses r-134a as the working fluid and operates on the ideal vapor-compression refrigeration cycle except for the compression process. the refrigerant enters the evaporator at 120 kpa with a quality of 34 percent and leaves the compressor at 70°c. if the compressor consumes 450 w of power, determine (a) the mass flow rate of the refrigerant, (b) the condenser pressure, and (c) the cop of the refrigerator. (0.00644 kg/s, 800 kpa, 2.03)