Can I please have it in an hour. And please indicate if you used excel or applets

Normal No Spacing Heading 1 Heading Paragraph Styles 1. (60 pts.) Two swimmers are recognized as among the best in a certain event. In a series of independent practice trials, they achieve the following times in seconds. Assume that the times are normally distributed. Swimmer A: 30.7 31.2 31.3 30.9 30.2 31.4 30.7 31.1 Swimmer B: 31.1 31.2 31.4 31.6 31.4 31.3 31.5 30.9 a. On the basis of these trials, can you detect a significant difference between the mean performance times of these two swimmers at the 1% significance level? b. Construct a 95% confidence interval for the difference in the mean times between the two swimmers. c. What is the point estimate for the difference in the mean times between the two swimmers? d. What is the margin of error for the confidence interval found in part (b)? e: Interpret the confidence interval for the difference in mean times obtained in part b. 2. (50 pts.) A researcher wanted to see whether cars that supposedly do not need high-octane gasoline get more miles per gallon using regular or high octane gas. They test several cars, using both types of gas in each car at different times. The mileage for each gas type for each car is in the following table. Assume the population distribution is normal. Car A B C D E F G H Regular 5 23 21 35 42 28 19 32 31 24 High-octane 18 21 25 34 30 19 27 34 20 a. Does using high-octane gasoline improve the gas mileage at the 5% significance level? b. Construct a 95% confidence interval for the mean difference in gas mileage. c. What is the point estimate of this interval? d. What is the margin of error of this interval