I also need c) construct a 99% confidence interval for the difference in the average prices for the two supermarket chains. (Round your answer to two decimals places) $_________ to $_________

An advertisement for a popular supermarket chain claims that it has had consistently lower prices than four other full-service supermarkets. As part of a survey conducted by an "independent market basket price-checking company," the average weekly total, based on the prices (in $) of approximately 95 items, is given for two different supermarket chains recorded during 4 consecutive weeks in a particular month. Week Advertiser ($) Competitor ($) 254.29 255.93 N 240.57 255.68 w 231.81 255.05 234.09 261.20 (a) Is there a significant difference in the average prices for these two different supermarket chains? (Use a = 0.05. Round your answers to three decimal places.) 1-2. Null and alternative hypotheses: O Ho: Hd = 0 versus Hai Hd 0 O Ho: Ha * 0 versus Hai Hd = 0 O Ho: Ha - 0 versus Hai Hd > 0 Ho: Hd = 0 versus Hai Hd # 0 3. Test statistic: t 4. Rejection region: If the test is one-tailed, enter NONE for the unused region. t > NONE X t