The following probabilities for grades in management science have been determined based on past records; Grade A, B, C, D, F and probability .10, .30, .40, .10, .10 . The grades are assigned on a 4,0 scale where an A is a 4.0 a B a 3.0 and so on. Determine the expected grade and variance. (2) A market in Boston orders oranges from Florida. The oranges are shipped to Boston from Florida by either railroad, truck or airplane, an order can take 1, 2, 3, or 4 days to arrive in Boston once it is placed. The following probabilities have been assigned to the number of days it takes to receive an order once it is placed( referred to as lead time) Lead time 1, 2, 3, 4 and probability .20, .s0, .20, ,1o. Compute the expected number of days to receive an order and the standard deviation.