11.9 Significance tests for regression coefficients. Refer to Exercise 11.1 (page 610). The following table contains the estimated coefficients and standard errors of their multiple regression fit. Each explanatory variable is an average of several five-point Likert scale questions.

Variable	Estimate	SE
Intercept	1.316	0.651
Math course anxiety	−0.212	0.114
Math test anxiety	−0.155	0.119
Numerical task anxiety	−0.094	0.116
Enjoyment	0.176	0.114
Self-confidence	0.118	0.114
Motivation	0.097	0.115
Feedback usefulness	0.644	0.194

(a) Look at the signs of the coefficients (positive and negative). Is this what you would expect in this setting? Explain your answer.
(b) What are the degrees of freedom for the model and error?
(c) Test the significance of each coefficient and state your conclusions.