7. (20 points) The following are 1116 average scores on 1116 mathematics part of 1116 Scholastic Aptitude Test (SAT) for some years from 1994 to 2007. m {a} Assuming a linear regression model for the year (X) and SAT score CY], please nd regression coefcients for 1116 linear model 1': A+BX {round to 3 decimafplaccs). {b} Give an interval that, with 95 percent condence, will contain the average SAT math score in 2005. (6} At 1116 10 percent signicance level, please test the hypolesis that 1116 year does not affect 1116 SAT score. In another word, please test that ,3 = D