The total amount of construction spending on highways and streets (in billions of dollars) is given in the accompanying table for the first six months of 2016. Month January February March April May June Spending 97 96 95 91 90 86 (a) Find the least-squares regression line that models these data, with x = 1 corresponding to January 2016. (b) Assuming the trend continues, estimate the amount of spending in December 2016. (a) The linear model for the data is y = ( ) x+ (Round to the nearest thousandth as needed.)