The total outstanding consumer credit of a certain country (in billions of dollars) can be modeled by the function C(x) = 9.44x^4 - 85.33x^3 + 287.29x^2 - 309.19x + 2651.5, where x is the number of years since 2008. The graph of C(x) is shown to the right. Complete parts (a) through (c). a) Find dC/dx. dC/dx = ? b) Interpret the meaning of dC/dx. Choose the correct answer below. A. The average rate of change of consumer credit in the year (2008 + x). B. The instantaneous rate of change of consumer credit in the year (2008 + x). C. The instantaneous rate of change of consumer credit in the year 2008. D. The average rate of change of consumer credit during the x years after 2008. c) Using this model, estimate how quickly outstanding consumer credit was rising in 2014. Outstanding consumer credit was rising by $? billion per year in 2014. (Simplify your answer. Type an integer or a decimal.)
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