During a 7-year period, the amounts (in millions of dollars) spent each year on buying new vehicles N and used vehicles U by United

States residents are modeled by the equations

N = -0. 028+3 +0. 06+2 +0. 17 +17

U = -0. 3862 +1. 50 +42

wheret

1 represents the first year in the 7-year period,

a. Write a polynomial that represents the total amount spent each year on buying new and used vehicles in the 7-year period.

The polynomial is

b. How much is spent on buying new and used vehicles in the fifth year?

$ million