Let x be the number of material anomalies occurring in a particular region of an aircraft gas-turbine disk. the article "methodology for probabilistic life prediction of multiple-anomaly materials"(amer. inst. of aeronautics and astronautics j.,2006: 787-793) proposes a poisson distribution for x. suppose that µ=4. a. compute both p(x≤4) and p(x< 4). b. compute p(4≤x≤ 8). c. compute p(8≤ x). d. what is the probability that the number of anomalies exceeds its mean value by no more than one standard deviation?