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The price per share of stock for a sample of 20 companies was recorded at the beginning of 2012 and then again at the end of the 1st quarter of 2012. How stocks perform during the 1st quarter is an indicator of what is ahead for the stock market and the economy. use the sample data in the table below to answer the following. Company Bank of New York Kraft Foods Consolidated Edison Johnson & Johnson Comcast Applied Materials Pfiser General Electric AT&T Home Depot JP Morgan Chase Procter & Gamble Verizon Devon Energy Lilly Coco Cola Qualcomm Exxon Mobil Pacific Gas & Electric Chevron End of 1st Quarter 24.13 38.01 58.42 65.96 30.01 12.45 43.41 20.07 31.23 50.31 45.98 67.21 38.23 71.12 40.27 74.01 68.06 86.73 22.65 107.21 Begining of Year 19.91 37.36 62.03 65.58 23.71 10.71 41.22 17.91 30.24 42.04 33.25 66.71 40.12 62.00 41.56 69.97 54.70 84.76 21.64 106.40 a. Let di denote the change in price per share for company i where di = end of 1st quarter of 2012 price per share minus the beginning of 2012 price per share. Use the sample mean of these values to estimate the dollar amount a share of stock has changed during the 1st quarter. (to 2 decimals) b. What is the 95% confidence interval estimate of the population mean change in the price per share of stock during the first quarter? Interpret this result. Standard deviation (to 3 decimals) Confidence interval (to 3 decimals) ( The mean price per share has increase between % over the three-month period (to 1 decimal).