(Choose 1 answer)
A retail store executive wants to know whether the store's average Internet sales exceed its average mail-order sales. A random sample of 15 Internet sales yielded a mean sale amount of $86.40 with a standard deviation of $18.75. A random sample of 10 mail-order sales yielded a mean sale amount of $75.20 with a standard deviation of $14.25.
Assume that the population variances are equal and that the two populations from which the samples are drawn are normally distributed. To determine whether the true mean Internet sale exceeds the true mean mail-order sale, which inferential statistical test is most appropriate?
A. two-sample independent t-test
B. two-sample z-test
C. two-sample proportion z-test
D. none of the above
