please help asap:

1)

Consider the system of components connected as in the accompanying picture. Components 1 and 2 are connected in series, so that subsystem works if and only if both 1 and 2 work; components 3 and 4 are also connected in series, so that subsystem works if and only if both 3 and 4 work. If components work independently of one another and P(component i works) = 0.85 for i = 1, 2 and = 0.93 for i = 3, 4, calculate P(system does not work).

2 3 4