A computer device can be either in a busy mode

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state

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$$processing a task, or in an idle mode

$($

state

$2$

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$$when there are no tasks to process. Being in a busy mode, it can finish a task and enter an idle mode any minute with the probability

$0$

$.$

$2$

$$; while being in an idle mode, it receives a new task any minute with the probability

$0$

$.$

$1$

$.$