A long-distance limousine company, Excalibur Limousine, owns four vehicles. These four vehicles are of different ages and have different repair records. The probabilities that on any given day, each vehicle will be available for business are 0.95 (for vehicle 1), 0.90 (for vehicle 2), 0.90 (for vehicle 3), and 0.80 (for vehicle 4). A. What is the expected number of vehicles available for business on a given day?
B. What is the variance of the number of vehicles available for business on a given day?
C. What is the probability that all four vehicles are available for service on a given day?
D What is the probability that at least one vehicle is available for service on a given day?