. Practice 1: Draw a picture describing the 99% confidence situation. What is a ? What is the area in one of the tails? What is the critical value za ?a Practice 2: Suppose we have data from a sample. The sample mean is 9.5, and the error bound for the mean is 2-75. what is the confidence interval estimate for the population mean? a Practice 4: The population standard deviation for the height of high school basketball players is 2.5 inches. If we want to be 98% confident that the sample mean height is within one inch of the true population mean height, how many randomly selected students must be surveyed