1) Classify the compressors according to refrigerant mass flow rate, pulse or continuous? 2) Draw the Pressure- volume diagram for the pulse and continuous refrigerant flow compressors.? 3) Why the manufacturers build low, medium, high backpressure compressors? What are the applications? 4) What is the difference between hermetic, semi-hermetic, and open compressors? What are their applications? 5) What are the main parts of the compressor?