Determine whether the function is one-to-one. If so, (a) write an equation for the inverse function in the form y=f1(x), (b) graph f and f1 on the same axes, and (c) give the domain and the range of f and f1. If the function is not one-to-one, say so. f(x)=x-4 (a) Write an equation for the inverse function in the form y=f1(x). Select the correct choice below and, if necessary, fill in any answer boxes to complete your choice. A. The function f(x) is one-to-one and f1(x)= | B. The function is not one-to-one. (Simplify your answer.)