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 Begining of Company End of 1st Quarter 24.13 Year Bank of New York 19.91 Kraft Foods 38.01 37.36 Consolidated Edison 58.42 62.03 Johnson & Johnson 65.96 65.58 Union Pacific 107.48 105.94 Applied Materials 12.45 10.71 Pfiser 43.41 41.22 AT&T 31.23 30.24 Cisco Systems 21.15 18.08 Home Depot 50.31 42.04 JP Morgan Chase 45.98 33.25 Procter & Gamble 67.21 66.71 Verizon 38.23 40.12 71.12 Devon Energy 62.00 Lilly 40.27 41.56 Microsoft 32.26 25.96 Coco Cola 74.01 69.97 Exxon Mobil 86.73 84.76 Pacific Gas & Electric 22.65 21.64 Chevron 107.21 106.40 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 % and % over the three-month period (to 1 decimal). 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 Begining of Company End of 1st Quarter 24.13 Year Bank of New York 19.91 Kraft Foods 38.01 37.36 Consolidated Edison 58.42 62.03 Johnson & Johnson 65.96 65.58 Union Pacific 107.48 105.94 Applied Materials 12.45 10.71 Pfiser 43.41 41.22 AT&T 31.23 30.24 Cisco Systems 21.15 18.08 Home Depot 50.31 42.04 JP Morgan Chase 45.98 33.25 Procter & Gamble 67.21 66.71 Verizon 38.23 40.12 71.12 Devon Energy 62.00 Lilly 40.27 41.56 Microsoft 32.26 25.96 Coco Cola 74.01 69.97 Exxon Mobil 86.73 84.76 Pacific Gas & Electric 22.65 21.64 Chevron 107.21 106.40 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 % and % over the three-month period (to 1 decimal)