Assuming the signal has been well-isolated, design a two-stage circuit to indicate heartbeat from an EKG signal. The first stage should amplify the biosignal to a 1V range (defined from Q-R), and the second will indicate heartbeat using a comparator. Assume the detection will occur using the R-wave of the signal. Describe how the output from the second stage indicates a heartbeat. Describe a possible third stage to provide an audible output indicating the heartbeat.

Refrigerant-134a enters the compressor of a refrigerator as superheated vapor at 0.14 mpa and -10°c at a rate of 0.05 ka/s and leaves at 0.8 mpa and 50°c. the refrigerant is cooied in the condenser to 0.72 mpa and 26'c. it is then throttled to 0.15 mpa. sketch the t-s diagram for the system and evaluate: 6) the rate of heat removai from the refrigerated space (kw), it) the power input to the compressor (kw), ii) the isentropic efficiency of the compressor (%), and iv) the cop of the refrigerator.