During the winter of2008-2009, the average utility bill for residents of a certain state was $198

per month. A random sample of 40customers was selected during the winter of2009-2010,and the average bill was found to be$188.99with a sample standard deviation of$21.44 (PLEASE USE THE EXCEL)

Complete parts a and b below.

a) Using alphaequals=0.05, does this sample provide enough evidence to conclude that the average utility bill in this state was lower in the winter of2009-2010 than it was in the winder of2008-2009? Determine the hypotheses. A. Upper H 0: mu equals 198=198 and Upper H 1: mu not equals 198198 B. Upper H 0: mu not equals 198198 and Upper H 1: mu equals 198=198 C. Upper H 0: mu greater than or equals 198198 and Upper H 1: mu less than 198<198 D. Upper H 0: mu less than or equals 198198 and Upper H 1: mu greater than 198

Determine the criticalvalue(s). The criticalvalue(s) is(are) ______. (Round to three decimal places as needed. Use a comma to separate answers asneeded.)

Determine the teststatistic, t Subscript x overbartx. t Subscript x overbartxequals=____ (Round to two decimal places asneeded.)

What conclusion should bedrawn?

A. RejectUpper H 0. There is sufficientevidence to conclude that the average utility bill in this state was lower in the winter of2009-2010 than it was in the winter of2008-2009. B. RejectUpper H 0. There is not sufficienevidence to conclude that the average utility bill in this state was lower in the winter of2009-2010 than it was in the winter of2008-2009. C. Do not reject Upper H 0. There is sufficientevidence to conclude that the average utility bill in this state was lower in the winter of2009-2010 than it was in the winter of2008-2009. D. Donotreject Upper H 0. There is not sufficientevidence to conclude that the average utility bill in this state was lower in the winter of2009-2010 than it was in the winter of2008-2009.

Use technology to determine thep-value for this test. p-value= (Round to three decimal places asneeded.)