An experiment was conducted to determine the effects of three methods of soil preparation on the first-year growth of lash pine seedlings. Four locations (state forest lands) were selected, and each location was divided into three plots. Since it was felt that soil fertility within a location was more homogeneous than between locations, a randomized block design was employed using locations as blocks. The methods of soil preparation were A (no preparation), B (light fertilization), and C (burning). Each soil preparation was randomly applied to a plot within each location. On each plot, the same number of seedlings were planted and the average first-year growth of the seedlings was recorded on each plot. Use the MINITAB printout to answer the questions.

a. Conduct an analysis of variance. Do the data provide evidence to indicate a difference in the mean growths for the three soil preparations?
b. Is there evidence to indicate a difference in mean rates of growth for the four locations?
c. Use Tukey's method of paired comparisons to rank the mean growths for the three soil preparations. Use a = .05.
d. Use a 95% confidence interval to estimate the difference in mean growths for methods A and B.

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Location Soil Preparation 1 2 3 11 13 16 10 15 17 20 12 10 15 13 10 Source Soil Prep Location Error Total DF MS 38.000 61.667 11.333 111.000 19.0000 10.06 0.012 20.5556 10.8 0.008 6 1.8889 S1.374 R-S 89.79 R-Sq (adj)81.28s Individual 95% CIs For Mean Based on Pooled StDev Soil Prep Mean 12.5 16.0 12.0 ( 2 12.0 14.0 16.0 18.0 Individual 95% CIs For Mean Based on Pooled StDev Location Mean --+--+----+- 12.0000 15.0000 16.3333 10.6667 ) 2 10.0 12.5 15.0 17.5