\\ I \\ I 7 I 2. Let Y be the lifetime, in minutes, of a lightbulb. Assume that the lightbulb has an expected lifetime of 2 hours and thatY is exponentially distributed. At 5:00pm, the lightbulb is installed and left on. At a random time during the lifetime of the bulb, Joe enters the room. (a). What time do you expect Joe Will enter the room? (b). Find the probability that Joe enters the room after 6:40pm