43. What type of contact is an emergency stop button? (a) Momentary, NC (b) Latching, NC (c) Momentary, NO (d) Latching, NO 44. Complete this statement: A starter is required when a motor is to be brought to a stop by means of plugging. 45. Which of the following braking systems can hold a motor stationary once it has stopped? (a) Dynamic braking (b) plugging (c) Friction brake (d) both a and b 46. For an electromechanical relay, the amount of voltage and current required to energize the relay coil is (a) more than what: required to de-energize the coil (b) less than what is required to de-energize the coil (c) the same as the voltage and current ratings of the contacts (d) the same when connected to an AC or a DC source 47. It is possible for a relay coil to be rated for 24 VDC and its contacts to be rated for 240 VAC (a) True (b) False

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Question 3: Suppose an engineer designed a fire alarm system for a large warehouse, with multiple pushbutton switches connected to a single alarm siren: Siren Actuating any of the normally-open switches results in the alarm sounding. So far, so good. Now, suppose that one of the wires connecting one side of several switches to the rest of the circuit breaks open. What will the result of this failure be? Siren break!

Please go into detail on What are Ring Counters, and Please show as many examples as possible.