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A turfgrass scientist is looking for an optimal approach tocontrol a certain plant disease in Kentucky blue grass. He comparesthree different management strategies designed so that they wouldreduce spread of the disease. He has set up a field study with atotal of 20 experimental plots and 4 treatments (3 diseaseprevention treatments and a control treatment. Each treatment hasbeen assigned to 5 randomly selected experimental plots. Plantbiomass is then measured from each pot at the end of theexperiment. ANOVA table and the treatment means are shownbelow.

ANOVA:

	DF	Sum of Squares	Mean Square	F Value	Pr > F
Treatment	3	5413.1
Error		536.0
Total

                

Treatment	Mean values of the plant biomass	Letters for part a)	Letters for part b)
Fertilizer rate 1	6.6
Fertilizer rate 2	21.2
Fertilizer rate 3	31.4
Control (no fertilizer)	2.2

a) Do all pairwise comparisonsbetween the treatment means using LSD, (a=0.05). Present theresults using letters assigned to treatment means (Put the lettersin the column Letters for part a) in the above table)

b) Do all pairwise comparisonsbetween the treatment means using Tukey’s HSD (a=0.05). Present theresults using letters assigned to treatment means. (Put the lettersin the column Letters for part b) in the above table)

c) Comment on differences inconclusions obtained using the two methods. Which method would youuse for this analysis? For full credit, provide anexplanation of your choice.