Researchers used data on the average reading and math scores on a national test for each state in a nation to develop a regression equation. The rearchers let the explanatory variable x be the average reading score and the response variable y be the average math score. The regression equation is ModifyingAbove y with caretequals19.6plus0.963x and the r-squared value is 0.917. a. One state had an average reading score of 498. Use the regression equation to predict the average math score for this state. b. This state had an average math score of 491.8. Calculate the residual associated with this state and comment on its value in the context of the problem. c. Does it appear that a state's average reading score is a reliable predictor of its average math score?