A Markov chain model for scoring a tennis game was studied in Section 10.1, Exercise 35. What are the communication classes for this Markov chain?

Data From Section 10.1 Exercise 35

To win a game in tennis, one player must score four points and must also score at least two points more than his or her opponent. Thus if the two players have scored an equal number of points (four or more), which is called “deuce” in tennis jargon, one player must then score two points in a row to win the game. Suppose that players A and B are playing a game of tennis that is at deuce. If A wins the next point it is called “advantage A,” while if B wins the point it is “advantage B.” If the game is at advantage A and player A wins the next point, then player A wins the game. If player B wins the point at advantage A, the game is back at deuce.