You grow 12 crystals from a solution and measure the length of each crystal in millimeters. Here is your data: 9, 2, 5, 4, 12, 7, 8, 11, 9, 3, 7, 4 What is the mean length of your crystals with a 95% confidence interval? 1. For each quantity x that has been measured N times, compute the sample average. 2. Then compute the sample standard deviation for each quantity. 3. Then compute the standard uncertainty for each quantity. 4. Compute an appropriate confidence interval