The cost, in millions of dollars, of a 30-second television ad during the Super Bowl in the years 1980 to 2000 can be approximated by C(t) = 0.044t + 0.222 million dollars (0 ≤ t ≤ 20) (t = 0 represents 1980).† What was the average cost of a Super Bowl ad during the given period? (Round your answer to three decimal places.)