Please help me with questions 1,2,3

3. [10 points] Calculate the overall reliability of the system shown below to four significant figures given the individual component reliabilities and assuming that failure of any component does not alter the reliabilities of other components: 0.9000 0.9000 0.9000 0.700 0.9000 0.7000 0.9000 0.9000 0.9000