3. For the following transition matrices determine the communicating classes (and Whether they are open or closed), absorbing states, tran- sient and positive recurrent states. (a) 1/2 0 0 1/2 0 1/2 1/2 0 0 0 1):: 1/4 1/2 0 0 1/4 0 0 0 1 0 0 0 1/2 1/4 1/4 (b) 0 1/3 0 1/3 1/3 1/3 1/3 0 1/3 0 1):: 0 0 2/3 0 1/3 1/4 1/4 0 1/4 1/4 0 0 1/3 0 2/3