f(t) = 10.72(0.9t + 10)0.3 (0 ≤ t ≤ 20)
where t is measured in years, with t = 0 corresponding to the year 2000.† At what rate was the percentage of Americans age 55 and older changing at the beginning of 2008? (Round your answer to four decimal places.)
____ % per year
At what rate was the percentage of Americans age 55 and older changing in 2017? (Round your answer to four decimal places.)
____% per year
What was the percentage of the population of Americans age 55 and older in 2017? (See Note on page 168. Round your answer to two decimal places.)
____%