An old extensive study conducted by a train transportation authority with thousands of passengers showed that a customer had to wait for an average of 10.3 minutes with a standard deviation of 6.2 minutes to buy their ticket. It is suspected that the current average waiting time is not 10.3 minutes anymore. A new random sample of 184 customers shows a mean of 9.3 and the same standard deviation of 6.2 minutes. Therefore we can safely assume that the population standard deviation is still 6.2 minutes. Use the 0.05 significance level. (a) In an attachment, write the null and alternative hypothesis, the formula for the test statistic, the decision rule