A non for profit company experiments with two procedures for contacting regular donors. In the first procedure, a phone call is made, the non-for-profit's objectives for the coming year are discussed and any questions are answered. The second procedure is similar, except that an agent of the non-for-profit arranges to meet with donors in their homes. For a random sample of 80 donors contacted by telephone the mean donation that resulted was $115 and the standard deviation was $71. For an independent random sample of 60 donors receiving a home visit, the mean and standard deviation of donations received were $131 and $83 respectively. Test the null hypothesis that the two populations means for donation value are equal against the alternative that they are not equal.
a. State the null and alternative hypothesis
b. Compute the test statistic
c. Compute the p-value and interpret it relative to the acceptance or rejection of the null hypothesis.