单选题
编号：2690456
1. When constructing a confidence interval for the population mean of a nonnormal distribution when the population variance is unknown and the sample size is large (n > 30), an analyst may acceptably use:
- A.Either a z-statistic or a t-statistic
- B.Only a z-statistic at
with n degrees of freedom - C.Only a t-statistic at /2 with n degrees of freedom