Question

A farmer applies three types of fertilizers on 4 separate plots. The figure
on yield per acre are tabulated below:
Plots
Fertilizers

Yield
A B C D Total
Nitrogen 6 4 8 6 24
Potash 7 6 6 9 28
Phosphates 8 5 10 9 32
Total 21 15 24 24 84

Find out if plots are materially different in fertility, as also, if the three
fertilizers make any material difference in yields
Given F0.05(2,6)=5.14 and F0.05(3,6)=4.76