Probability. Solve using queueing theory

The fair has one last game, a duck pond, which can handle 3 players at once. The players arrive according to a Poisson process with a rate of 75 per hour, and the time it takes to play is exponential with a mean of 2 minutes. The players are mostly impatient children, so if there are 4 people in line when they arrive, they will leave immediately. a. What is the probability that there will be no players at the game when a new player arrives? b. On average, how many people are waiting in line? c. On average, how long will a player wait in line before beginning to blay (in minutes)? d. On average, how many players balk (leave without playing) in 4 hours