A journal published a study of the lifestyle of visually impaired students. Using diaries, the students kept track of several variables, including the number of hours of sleep obtained in a typical day. These visually impaired students had a mean of 9.41 hrs and a standard deviation of 2.09 hrs. Assume that the distribution of the number of hours of sleep for this group of students is approximately normal.
A. Find P(8< x<10)
B. Find the value a for which P(x < a) = 0.3