13.91 [EX13-01] Refer to the wheat crop data in Section 13.1 on page 696.

a. Construct a scatter diagram and find the linear correlation coefficient and the equation for the line of best fit for Planted (x) and Production

(y).

b. Find the 95% confidence interval for the true linear correlation coefficient between Planted and Production.

c. Calculate the 95% confidence interval for the slope, 1, for the line of best fit relating Planted and Production.

d. Predict the total production for a county with 125 thousand acres planted using a 95% prediction interval.

e. Construct a scatter diagram and find the linear correlation coefficient and the equation for the line of best fit for Planted (x) and Yield (y).

f. Test the significance of the correlation between Planted and Yield. Use   0.05.

g. Test the significance of the slope, 1, for the line of best fit relating Planted and Yield. Use

  0.05.

h. Estimate the mean yield for all counties with 100 thousand acres planted with a 95% confidence interval.