How to solve these problems? Last year, the mean dollar spent for online purchases on the AMAZING WEBSITE for the week (7 days) before JULY 4TH among customers who use their Vista Charge Card was $850. The population standard deviation is not known. Because of increased use of on-line purchasing, Vista's Vice President of Electronic Marketing believed that purchasing on the AMAZING WEBSITE has changed. He randomly selects 400 customer accounts. The results of the sample found that customers that used Vista charge card spent a mean dollar amount of $862 on purchases with s = $80 (use alpha 1%) a) State the null and alternative hypothesis in symbols and in words. b) Calculate the expected results for the hypothesis test sampling distribution, assuming the null hypothesis is true. (i.e., name and graph of sampling distribution, mean and standard error) c) Identify the standard distribution that best approximates the sampling distribution. d) Formulate the decision rule(use can use either critical test scores or p-values) e) Determine the statistical results: test statistic, critical test statistic and p-value f) Determine the conclusion in terms of the null and alternative hypotheses. Do the sample results indicate that the vice president's claim is supported at alpha = 1%