Confidence Interval question~ need help. Thanks you~~

1.

The manufacturers of Good-O use two different types of machines to fill their 25 kg packs of dried dog food. On the basis of random samples of size 12 and 14 from output from machines 1 and 2 respectively, the mean and standard deviation of the weight of the packs of dog food produced were found to be 23.494 kg and 0.151 kg for machine 1 and 25.653 kg and 0.101 kg for machine 2. Hence, under the usual assumptions, determine a 98% confidence interval for the difference between the average weight of the output produced by machine 1 and by machine 2. Construct the interval as the average weight of machine 1 minus machine 2, stating only the lower limit of the interval correct to3 decimal places.

2.

ANZ Bank's Wealth Management Division conducted a survey of the value of the new business created over the last month in millions of dollars. From 23 responses, the mean and standard deviation were found to be $1.987 and $0.41 million respectively. Assuming the data were collected through a random sample and that the value of new business is approximately normally distributed, calculate a 95% confidence interval estimate of the average value of new business per month in millions of dollars. State only the upper bound correct tothree decimal places.