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. The accompanying file contains relevant data.

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

Note: Round your answers to 2 decimal places.

height=

+

fertilizer

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

Note: Negative values should be indicated by a minus sign. Round your answers to 2 decimal places.

height=

+

fertilizer+

fertilizer2

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

Note: Round coefficient estimates to at least 4 decimal places and final answer to 2 decimal places.

fertilizer amount=

ounces

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.

Note: Round coefficient estimates to at least 4 decimal places and final answer to 2 decimal places.

height=

inches

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