Terri Vogel, an amateur motorcycle racer, averages 129.96 seconds per 2.5 mile lap (in a 7 lap race) with a standard deviation of 2.28 seconds . The distribution of her race times is normally distributed. We are interested in one of her randomly selected laps. (Source: log book of Terri Vogel) Let X be the number of seconds for a randomly selected lap. Round all answers to 4 decimal places where possible.

a. What is the distribution of X? X ~ N(,)

b. Find the proportion of her laps that are completed between 126.48 and 127.95 seconds.

c. The fastest 2% of laps are underseconds.

d. The middle 50% of her laps are fromseconds toseconds.