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Let {X_1 (t),t=0} and {X_2 (t),t=0} be independent two-state continuous-time Markov Chains on the states 0 and 1 having the same generator matrix
G= (¦(-?&?@µ&-µ))
Define Y(t)= X_1 (t)+ X_2 (t) at any time t
Argue that {Y(t),t=0} is a continuous-time Markov Chain on the states {0,1,2} and determine its generator matrix.

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