Hint: Use the definition of f(x) and the mean value theorem. Suppose g(x) = ax² + (1/2)cos(5x) + 20sin(x), where a > 0. If g(x) = 0, what are the possible values of a?

A) 0.001, 0.002, 0.003, ..., 0.009, 0.010
B) 0.001, 0.002, 0.003, ..., 0.009
C) 0.001, 0.002, 0.003, ..., 0.010
D) 0.001, 0.002, 0.003, ..., 0.011