An article in the San Jose Mercury News stated that students in the California state university system take
4.8 years, on average, to finish their undergraduate degrees. A freshman student believes that the mean
time is less and conducts a survey of 39 students. The student obtains a sample mean of 4.3 with a sample
standard deviation of 1.8. Is there sufficient evidence to support the student's claim at an a = 0.05
significance level?