The following data are the lengths of the menstrual cycle in a random sample of 15 women. Test the hypothesis that the mean length of human menstrual cycle is equal to a lunar month (29.5 days).

The data are 26, 24, 29, 33, 25, 26, 23, 30, 31, 30, 28, 27, 29, 26, and 28 days.

Hint: You can assume that {X1, X2, ..., X15} is a Simple Random Sample from a Normal population. That is X1~Normal [ , ].

compute a 95% upper confidence bound for .

Note that "Inf" represents "infinity".

Group of answer choices

(-Inf , 27.323)

(-Inf , 25.602)

(-Inf , 26.527)

(-Inf , 28.914)

(-Inf , 29.429)