Total expenditures in a country (in billions of dollars) are increasing at a rate of f(x)=9.38x+87.11, where x=0 corresponds to the year 2000. Total expenditures were $1584.88 billion in 2002. a. Find a function that gives the total expenditures x years after 2000. b. What will total expenditures be in 2013? a. What is the function for the total expenditures? F(x)= (Simplify your answer. Use integers or decimals for any numbers in the expression.) b. In 2013, total expenditures will be $billion.