3. In a car dealer, the number of cars sold (x) by a sale person in a week follows a probability distributionbelow. (a) [4 points] Find the probability that the

number of car sales in a week exceeds 2. (b) [4 points] Calculate the expectation of the number of cars sold by a sales person in a week. (c) [6 points] Calculate the standard deviation of the number of cars sold by a sale person in a week.