A random sample of 17 snowmobiles was selected, and the lifetime of the battery was measured. The variance of the sample was 9.7 months. Find the 95% confidence interval of the true variance. Please include all work showing how you found vour answer

A bottle of water is advertised as containing 1 liter of water.  However, after testing a few hundred bottles, you find the average amount of water is normally distributed and contains 1.07 liters on average with a standard deviation of 0.05. What percent of bottles have exactly 1 liter? Please solve in excel.

Choose the appropriate statistical test. When computing, be sure to round each answer as indicated. A dentist wonders if depression affects ratings of tooth pain. In the general population, using a scale of 1-10 with higher values indicating more pain, the average pain rating for patients with toothaches is 6.8. A sample of 30 patients that show high levels of depression have an average pain rating of 7.1 (variance 0.8). What should the dentist determine? 1. Calculate the estimated standard error. (round to 3 decimals). [st.error] 2. What is thet-obtained? (round to 3 decimals). 3. What is the t-cv? (exact value) 4. What is your conclusion? Only type "Reject" or Retain"

A study of a local high school tried to determine the mean number of text messages that each student sent per day. The study surveyed a random sample of 114 students in the high school and found a mean of 195 messages sent per day with a standard deviation of 73 messages. Determine a 95% confidence interval for the mean, rounding all values to the nearest whole number.

It has been reported that the variance of the speeds of drivers on the Turnpike near Somerset, PA is 64 for all vehicles. A driver who was pulled over near Somerset on the pike feels that value is incorrect and conducts a 4. survey of speeds. He finds that the standard deviation of 50 vehicles is 10.5 mph. At a 0.05, is the driver correct? %3D

For a group of 20 students taking a PSDTF test, the mean heart rate was 96 beats per minute, and the standard deviation was 5. Find the 95% confidence interval of the true mean.