Answer Happy

J.J.Bean sells a wide variety of outdoor equipment and clothing. The company sells both through mail order and via the internet. Random samples of sales receipts were studied for mail-order sales and internet sales, with the total purchase being recorded for each sale. A random sample of 1818 sales receipts for mail-order sales results in a mean sale amount of $89.90$⁢89.90 with a standard deviation of $19.75$⁢19.75. A random sample of 1010 sales receipts for internet sales results in a mean sale amount of $84.90$⁢84.90 with a standard deviation of $26.75$⁢26.75. Using this data, find the 99%99% confidence interval for the true mean difference between the mean amount of mail-order purchases and the mean amount of internet purchases. Assume that the population variances are not equal and that the two populations are normally distributed.
Construct the 99%99% confidence interval. Round your answers to two decimal places.