According to a National Survey,the Average Commuting Time for People

According to a national survey,the average commuting time for people who commute to a city with a population of 1 to 3 million is 19.0 minutes.Suppose a researcher lives in a city with a population of 2.4 million and wants to test this claim in her city.Taking a random sample of 20 commuters,she calculates a mean time of 19.346 minutes and a standard deviation of 2.842 minutes.Calculate the appropriate test statistic to test the hypotheses.