ny surveyed the prices for a quart of a certain brand of motor oil. The sample data, in dollars per quart, is summarized in the table below. Price per Quart Number of (dollars) Stores 1.99 2 2.09 5 2.19 11 2.29 13 2.39 8 2.49 3 (a) Find the mean and the standard deviation of the prices. (Round your answers to three decimal places.) mean $ standard deviation $ (b) What percent of the data lies within one standard deviation of the mean? (Round your answer to the nearest whole number.) % (c) What percent of the data lies within two standard deviations of the mean? (Round your answer to the nearest whole number.) % (d) What percent of the data lies within three standard deviations of the mean? (Round your answer to the nearest whole number.) %