If the power to a condensing unit has been turned off for an extended period of time, the should be energized first for the recommended time to protect the compressor from liquid floodback. A. blower motor B. thermostat C. crankcase heater D. condenser fan motor

Apiping systems consists of 6 m of 6-std type k and 12 m of 4-std type k, both drawn copper tubing. the system conveys ethylene glycol at a rate of 0.013 m3/s. the pressure drop across the system is to be calculated. there are two 90° elbows in the 6-in pipe, a reduction from the 6-in pipe to the 4-in pipe and four 90° elbows in the 4-in pipe. all fittings are soldered (same as flanged) and regular. the inlet and outlet of the system are at the same height.