aThe lifetime T in hours to a particular brand of radio batt

a)The lifetime T (in hours) to a particular brand of radio batteries (1.5V) can be assumed to be N(117.2, 102). In Mrs. Jenssen radio there are 8 such batteries. She knows that the radio works if at least 4 of the batteries are working. What is the probability that Mrs Jenssens radio seems at the start of the men\'s relay in Norway, unless it is 130 hours since she replaced all the batteries, and the life of those assumed to be independent? Justify your choice of model (distribution).

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