A green pepper farmer is designing an experiment to determine the effect of a certain fertilizer on the production of his pepper plants.He has already planted 20 large green pepper plants in a rectangular plot with 5 rows and 4 columns (see diagram below).He wants to use 5 different levels of fertilizer (0, 1, 2, 3, 4 ounces per plant per week).

a. Explain to the farmer how he should assign the 5 treatments to the 20 pepper plants in the field using a completely randomized design.

b. What is the purpose of the random assignment in this experiment?

c. Suppose that the results of the experiment show that there is a statistically significant positive relationship between the amount of fertilizer and the production of the plants.Explain the meaning of "statistically significant" in this context.

After conducting this experiment for three months, the farmer calculates the total production of each plant (measured in pounds).This information is summarized in the output below.

The regression equation isPepper (pounds) = 10.4 + 1.85 Fertilizer (ounces)

Predictor Coef SE Coef T P

Constant 10.3500 0.6917 14.96 0.000

Fertilizer(ounces) 1.8500 0.2824 6.55 0.000

S = 1.78590R-Sq = 70.5%R-Sq(adj) = 68.8%

Scatterplot of Peppers vs Fertilizer

• the y-axis of the first scatterplot: peppers (pounds)

\f\f\f