A sports drink maker claims that the mean calorie content of its beverages is 72 calories per

Question:

A sports drink maker claims that the mean calorie content of its beverages is 72 calories per serving.
Determine whether the claim represents the null hypothesis or the alternative hypothesis. If a hypothesis test is performed, how should you interpret a decision that
(a) Rejects the null hypothesis?
(b) Fails to reject the null hypothesis?