A horticulturist is studying the relationship between tomato plant height and fertilizer amount. Thirty tomato plants grown in similar conditions were subjected to various amounts of fertilizer (in ounces) over a four-month period, and then their heights (in inches) were measured. A portion of the results is shown in the accompanying table.

a. Estimate the linear regression model: Height = ₀ + ₁Fertilizer + .

b-1. Estimate the quadratic regression model:Height = ₀ + ₁Fertilizer + ₂Fertilizer² + .

b-2. Using the quadratic results, find the fertilizer amount at which the height reaches a minimum or maximum.

c. Use the best-fitting model to predict, after a four-month period, the height of a tomato plant that received 3.0 ounces of fertilizer.

Height	Fertilizer
20.4	1.9
29.1	5.0
28.2	4.2
24.3	1.3
29.2	4.9
29.8	5.4
34.6	3.1
25.3	0.0
26.2	2.3
25.7	2.5
26.5	0.9
28.6	1.0
25.7	4.5
36.8	3.8
27.2	5.3
33.4	2.3
25.1	4.0
22.1	1.4
40.6	3.9
24.5	4.0
39.7	3.6
21.1	0.6
25.4	1.6
29.6	2.5
27.6	4.5
32.6	3.6
33.5	2.0
22.5	0.0
27.6	2.5
36.4	3.1