Consider the following sample regression line: T = 80.1 + 2.28 ST, where T is the score on a test and ST is the number of hours studying for it. The null hypothesis is that the slope coefficient equals zero. You are told that thet-statistic on the slope coefficient is 4.38. What is the standard error of the slope coefficient?

A. 0.52

B. 1.96

C. 1.92

D. 1.52

If you have a two variable population regression model, but exclude one variable from the regression, this _____

A. will have no effect on the coefficient of the included variable if the correlation between the excluded and the included variable is negative.

B. will always bias the coefficient of the included variable upwards.

C. will have no effect on the coefficient of the included variable if both X variables are independent from each other.

D. makes the sum of the product between the included variable and the error terms different from 0.