3. Suppose the time it takes a nine-year-old to eat a donut is between 1 and 4 minutes. Let X be the time, in minutes, it takes a nine-year-old to eat a donut and X-U(1,4). Find the probability function f(x), and the average/medium X over the support range. Find the probability that a different nine-year old child eats a donut in more than 2 minutes given that the child has already been eating the donut for more than 1.5 minutes