The mean income per person in the United States is $42,500, and the distribution of incomes follows a normal distribution. A random sample of 12 residents of Wilmington, Delaware, had a mean of $53,500 with a standard deviation of $11,000. At the 0.050 level of significance, is that enough evidence to conclude that residents of Wilmington, Delaware, have more income than the national average?

a.State the null hypothesis and the alternate hypothesis.

H0: _____

H1: > _____

b.State the decision rule for 0.050 significance level.(Round your answer to 3 decimal places.)

Reject H0 if t > __________

c.Compute the value of the test statistic.(Round your answer to 2 decimal places.)

d.Is there enough evidence to substantiate that residents of Wilmington, Delaware, have more income than the national average at the 0.050 significance level? PICK THE CORRECT PHRASE TO COMPLETE THE SENTENCE.

(Reject, Do not reject) H0. There is (sufficient, insufficient) Evidence to conclude that the mean income in Wilmington is (greater than, less than) $42,500.