Hospital Noise Levels For a sample of 7 operating rooms taken in a hospital study, the mean noise level was 42 decibels and the standard deviation was 10.1. Find the 95% confidence interval of the true mean of the noise levels in the operating rooms. Assume the variable is normally distributed. Round your answers to at least two decimal places. Ed X 5Thunderstorm Speeds A meteorologist who sampled 8 thunderstorms found that the average speed at which they traveled across a certain state was 15 miles OO per hour. The standard deviation of the sample was 2.9 miles per hour. Round the final answers to at least two decimal places. Part: 0 / 2 Part 1 of 2 Find the 80% confidence interval of the mean. Assume the variable is normally distributed.