3. An agronomist fits a simple linear regression model for crop yield, measured in tons of wheat, and fertilizer, measured in hundreds of pounds. The data set contains 26 observations and produces the following results:

Y = 50 + 4 XS_e = 1.25X bar = 210 (X - X bar)² = 2500

a. What is the independent variable? ________________ (2 pts)

b. What is the dependent variable? _________________ (2 pts)

c. Interpret the estimated value of the true population slope coefficient?

d. Suppose we wish to test whether or not there is a positive relationship between these two variables. What hypotheses would you use?

H_O:H_A:

e. What sampling distribution would apply to the test in part d?

f. What is the CRITICAL value if alpha = 0.01?

g. What is the CALCULATED value to compare to your answer in part (f)?

h. What would be the value of the measure of dispersion used to build a confidence interval for a mean value of Y when the independent variable equals 210? (