The number of customers in line at a supermarket express checkout counter is a random variable with the following probability distribution. P(X=k) 0.10 0.25 0.30 0.20 0.10 0.05 a} P(X=2]= b) The probability that strictly;r more than three customers are in line at the express checkout is c) In the long run, the number of customers in line at the express checkout is , on average. d} P(X=0 U X=4)= e) The probability that one or less customers are in line at the express checkout is