(8 points) 2. An environmentalist is interested in estimating the mean time between ALL eruptions of Old Faithful Geyser in Yellowstone National Park. Over the course of a year, she takes a random sample of the time intervals (in minutes) between eruptions. Her results are recorded in the following table. Both the population mean and standard deviation are unknown. Time Between Eruptions (in minutes) 63 63 71 77 81 65 67 84 72 75 70 70 93 83 85 79 90 74 81 74 80 65 70 84 83 78 71 67 97 88 62 61 57 86 70 77 78 75 67 89 93 81 86 65 70 77 83 76 76 67 99 75 76 83 97 93 73 81 85 90 (a) Construct a stem-and-leaf diagrams of the times using two lines per stem. (b) Describe the stem-and-leaf diagram. When describing a graph, you must describe the shape, center and spread. Problem continued on next page... 2