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Subsystems A and B comprise a piping system, and both must operate for the piping system to be functional. Subsystem A consists of three identical pumps and functions as long as at least two pumps are functional. Subsystem B consists of three identical valves and functions as long as at least one valve is functional. Assume that the reliability of each pump and each valve over the life of piping system are 0.7 and 0.8, respectively. a) Calculate the reliability of the piping system b) If subsystem B is replaced with new one, in which two valves are connected in parallel, fnld the reliability of the new piping system