1.) Passenger congestion is a service problem in airports. Trains are installed within the airport to reduce the congestion. With the use of the train, the time X in minutes that it takes to travel from the main terminal to a particular concourse has density function f(x)=0.1, 0
2.) A traffic control engineer reports that 75% of the vehicles passing through a checkpoint are from within the state. Let X be the number of vehicles from out of state of the next 10 vehicles. Then the sum of mean and variance of X is