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QUESTION 2 During the real estate run-up in 2000-2008 the percentage of mortgages issued in the United States that were subprime (normally classified as risky) could be 15 approximated by A(t) = percent for O s t S 8 f years after the start of 2000, 1 + 8.6(1.8)-t (a) How fast, to the nearest 0. 1%, was the percentage increasing at the start of 2002? percent/year (b) How fast, to the nearest 0. 1%, was the percentage increasing at the start of 2006? percent/year