4. In 2021, CollegeData.com reported that books and materials cost an average of $1,240 a year for students attending public or private, four-year colleges. Assume that the cost of books is normally distributed with a standard deviation of $105. What is the probability that a single student chosen at random reports textbooks and materials costing more than $1362 for an academic year? b. Assuming the mean and standard deviation of textbook costs have not changed, completely describe the sampling distribution for the annual mean amount spent on books for a random sample of 15 students. determ minig home to nigam tellsme to megil & syed of lavisini sanobfines age s tagus boy of Towers 180Y C. What is the probability that the annual mean cost of textbooks and materials for a random sample of 15 students is greater than $1362? Chenyour probability In part(b) on prevalent wow than rap d. Considering your answer in part c, would you be willing to conclude that the annual average co of textbook prices is more than $1240? Why or why not