The average waiting time per customer at the fast food restaurant has been 7.5 minutes. The customer waiting time has the normal distribution. The manager claims that the employ of the new cashier system will reduce the average customer waiting time in the store. Based upon a random sample of 16 customer transactions the mean waiting time is 6.3 minutes and standard deviation is 2 minutes per customer. Test the manager's claim at 5% as well as 1% significance level tests.