(b) A metallurgical engineer believe too many steel specimens produced by an older process will fail to meet a new, more stringent strength, standard imposed by a customer. An inspector selects four specimens for destructive testing. The table, based on the engineer's best guess, describe the distribution of the number of specimens in the sample that fail to meet the specification: y 3 4 P(y) 0.1022 0.3633 0.3814 o.1387 0.0144 (i)Find the probability that at least three specimen fail to meet the new specification (ii) Find the probability that fewer than two fail to meet the new specification (iii) Find mean and variance for the number of specimens that fail to meet the new specification.