A state education agency designs and administers high school proficiency exams. Historically, time to complete the exam was an average of two hours with a standard deviation of 5 minutes. Recently the format of the exam changed and the claim has been made that the time to complete the exam has changed. A sample of 50 new exam times yielded an average time of 118 minutes. Calculate a 99% confidence interval based on the sample result.
[117.61 120.09]
[117.36 119.39]
[116.18 119.82]
[115.67 120.33]
[115.82 120.18]