A study was conducted to compare the effect of four manganese rates ( from MnSO4) and four copper rates ( from CuSO4 5H2O) on the yield of soybeans. A large field was subdivided into 32 separate plots. Two plots were randomly assigned to each of the 16 factor€“level combinations (treatments) and the treatments were applied to the designated plots. Soybeans were then planted over the entire field in rows 3 feet apart. The yields from the 32 plots are given here (in kilograms/ hectare).

a. Identify the design for this experiment.
b. Write an appropriate statistical model for this experiment.
c. Construct a profile plot and describe what this plot says about the effect of Mn and Cu on soybean yield.

Mn 80 110 Cu Mean 1558 2.003 2.490 2.830 1,578 2,033 2,470 2,81 2215 1,590 2,020 2620 2,860 1,610 205 2,632 ,84 2,2780 1,5582,003 2,490 2,830 1550 2.010 690 2,910 2255.1 1328 2,010 ,887 2.960 1427 2,0312,832 2,941 2,302.0 Mn Mean 524.9 2,020. 2,638.9 2872.8 2,264.2