PLS HELP I'LL GIVE U BRAINLIEST

Write a recursive sequence that represents the sequence defined by the following explicit formula:

Aparallel system functions whenever at least one of its components works. consider a parallel system of n components, and suppose each component works independently with probability 0.5. find the conditional probability that component n works given that the system is working

How many credit hours will a student have to take for the two tuition costs to be equal? round the answer to the nearest tenth of an hour.