= - Assume that the failure time of a sensor for energy distribution follows an exponential distribution with failure rate 2 = 6.84 x 10-2year-1. Assume two independent and identical sensors measuring a physical parameter of a control loop. When the main sensor fails it is immediately replaced by the standby one, which can also fail while in standby with rate is = 10-2year-1. Consider one repair worker that can repair a sensor whose failure is revealed with a repair rate u 10-2year-1, o Draw the Markov diagram of the system upon proper definition of the system states; o Compute the system steady-state availability (8 pts). =