Let (X1(t), t0), (X2(t), t0) and (X3(t), t0) be continuous-time Markov chains with state spaceS={1,2,3}and infinitesimal generatorsQ1,Q2,

Let (X1(t), t ≥ 0), (X2(t), t ≥ 0) and (X3(t), t ≥ 0) be continuous-time Markov chains with state space S = {1, 2, 3} and infinitesimal generators Q1, Q2, and Q3 respectively, where

For each of these three Markov chains, indicate whether or not the Markov chain is irreducible. Explain your answers.