A marketing research firm whishes to compare the prices charged by 2 supermarket chains Publi's and Wally's. The research firm using a standardized one week shopping plan (grocery lists, makes identical purchases at 100 of each chain's stores. The stores for each chain are randomly selected, and all purchases are made during a single week. It is reasonable to assume that the samples are independent. Weeky Expenses Publi's Average Weekly Expenses of the 100stores Sample Variance $120.86 $3.36 $116.43 Wally's Average Weekly Expenses of the 100 stores Sample Variance $7.85 At 95% confidence what is the margin of error - Round to 4 decimal places If you can use up to 2 decimals in your intermediate calculations