The efficiency for a steel specimen immersed in a phosphating tank is the weight of the...

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The efficiency for a steel specimen immersed in a phosphating tank is the weight of the phosphate coating divided by the metal loss (both in mg/ft). An article gave the accompanying data on tank temperature (X) and efficiency ratio (y). Temp. 180 181 184 184 184 184 184 185 185 186 186 186 186 188 188 189 190 192 Ratio 0.96 1.70 1.37 1.58 1.57 2.15 2.17 0.80 1.35 0.86 1.73 1.92 2.58 1.55 2.42 2.92 1.91 3.08 Consider this simple linear regression model to answer the following questions. = Ratio Bo+B1* Temperature + , where N(0, 0) (a) Determine the slope and intercept of the estimated regression line. (Round your answers to 5 decimal places, if needed.) slope: intercept: (b) Calculate a predicted value for efficiency ratio when tank temperature is 186. (Round your answers to 4 decimal places, if needed.) = (c) Calculate the values of the residuals from the least squares line for the four observations for which temperature is 186. (Round your answers to 4 decimal places, if needed.) (186, 0.86): (186, 1.73): (186, 1.92): (186, 2.58): Why do they not all have the same sign? O Some observed values are below the regression line while others are above the regression line. Some observed values are below the temperature average while others are above the regression line. Some predicted values are below the regression line while others are above the regression line. O Some predicted values are below the temperature average while others are above the regression line. The efficiency for a steel specimen immersed in a phosphating tank is the weight of the phosphate coating divided by the metal loss (both in mg/ft). An article gave the accompanying data on tank temperature (X) and efficiency ratio (y). Temp. 180 181 184 184 184 184 184 185 185 186 186 186 186 188 188 189 190 192 Ratio 0.96 1.70 1.37 1.58 1.57 2.15 2.17 0.80 1.35 0.86 1.73 1.92 2.58 1.55 2.42 2.92 1.91 3.08 Consider this simple linear regression model to answer the following questions. = Ratio Bo+B1* Temperature + , where N(0, 0) (a) Determine the slope and intercept of the estimated regression line. (Round your answers to 5 decimal places, if needed.) slope: intercept: (b) Calculate a predicted value for efficiency ratio when tank temperature is 186. (Round your answers to 4 decimal places, if needed.) = (c) Calculate the values of the residuals from the least squares line for the four observations for which temperature is 186. (Round your answers to 4 decimal places, if needed.) (186, 0.86): (186, 1.73): (186, 1.92): (186, 2.58): Why do they not all have the same sign? O Some observed values are below the regression line while others are above the regression line. Some observed values are below the temperature average while others are above the regression line. Some predicted values are below the regression line while others are above the regression line. O Some predicted values are below the temperature average while others are above the regression line.