Question: Willows in Yellowstone Writers in some fields summarize data by giving x - and its standard error rather than x - and sx. Biologists studying willow plants in Yellowstone National Park reported their results in a table with columns labeled x - ± SE. The table entry for the heights of willow plants (in centimeters) in one region of the park was 61.55 ± 19.03.21 The researchers measured a total of 23 plants.
(a) Find the sample standard deviation sx for these measurements. Show your work.
(b) A hasty reader believes that the interval given in the table is a 95% confidence interval for the mean height of willow plants in this region of the park. Find the actual confidence level for the given interval.