A food manufacturer processes and packets boxes of granola. The net weight of a standard box of granola is supposed to be 420g but a random sample of 36 boxes gave an average weight of 415g with a standard deviation of 25g. Is there any evidence that the true mean weight is not 420g? (Use a 5% significance level). a) Formulate your Null and alternative hypotheses b) Which test are you conducting: a Z-test or a t-test and why? c) What is the standard error? d) What is the Z-statistic? e) What is your statistical decision and why