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A student wants to compare textbook prices for two onlinebookstores. She takes a random sample of five textbook titles froma list provided by her college bookstore, and then she determinesthe prices of those textbooks at each of the two websites. Theprices of the five textbooks selected are listed below in the sameorder for each online bookstore.

A.com: $115, $43, $99, $80, $119

B.com: $110, $40, $99, $69, $109

(a) Are these independent or dependent samples?

Independent. The same textbooks are being compared.Dependent.The same textbooks are beingcompared.    Independent. Different textbooksare being compared.Dependent. Different textbooks are beingcompared.

(b) To construct a confidence interval, conditions for the datamust be checked. Which variable should be checked?

the difference between the textbook price from A.com and thetextbook price from B.com for each textbook.the prices of textbooksfrom B.com    the prices of textbooks fromA.comthe difference between the average textbook price for A.comand the average textbook price for B.com

(c) Find a 94% confidence interval for the mean difference intextbook prices at the two online bookstores. (Use d = A.com -B.com.) HINT: Use StatCrunch. Enter the two columns of numbers,Stat > t stat > choose the appropriate test and fill inwhat's needed (   ,   ) (Use 3decimal places)

(d) Suppose conditions are met. Using α = 0.06, is there evidenceto indicate that the mean price of textbooks for A.com differs fromthe mean price of textbooks for B.com?

Because the interval does not contain zero, it is not plausiblethat the mean difference between A.com and B.com is 0. There isevidence to indicate that the mean price of textbooks for A.com isdifferent from the mean price of textbooks for B.com .Because theinterval contains zero, it is not plausible that the meandifference between A.com and B.com is 0. There is evidence toindicate that the mean price of textbooks for A.com is differentfrom teh mean price of textbooks forB.com.    Because the interval does not containzero, it is plausible that the mean difference between A.com andB.com is 0. There is not enough evidence to indicate that the meanprice of textbooks for A.com is different from the mean price oftextbooks for B.com.Because the interval contains zero, it isplausible that the mean difference between A.com and B.com is 0.There is not enough evidence to indicate that the mean price oftextbooks for A.com differs from the mean price of textbooks forB.com.