Grace is the manager at a local restaurant and has implemented changes to her operation to reduce the average wait time for a table between 6pm and 8pm on Saturday night to less than 20 minutes. A random sample of 45 wait times on Saturday night had a mean of 18.3 minutes. Grace knows from past experience that the standard deviation of wait times is 5 minutes. Conduct a hypothesis test using p-value and critical value approach to determine if Grace's changes have reduced average wait time to less than 20 minutes using = 0.01