4. (20 points) A particular contraption has three buttons (red, blue, and green) and a three-button- sequence combination. When the correct combination is entered, a light goes on and then turns off; the contraption then returns to its initial state. If, instead, the wrong combination is entered, a buzzer sounds; the contraption then ends up in a permanently dead state. This contraption is very similar to the one [that will be] discussed in lecture, with the following primary exception: in the case of a wrong combination, the buzzer sounds only after three buttons have been pressed. In addition, this contraption has a different combination. Use the events {red, blue, green, on, off , buzz} to write a CCS process for such a contraption, where the correct combination is blue, blue, red. Your answer should include both (i) the CCS process itself and (ii) its transition graph. Caveat: Make sure your process is always prepared to accept any button whenever a combination is being entered. a