If $f$ and $g$ are functions, suppose we know the following things: $$\begin{aligned} f(7) \amp= 12 \amp f(5) \amp= 15 \amp g(8)\amp= 13 \amp g(4)\amp= 17 \end{aligned}$$

1. What is $f^{-1}(15)\text{?}$
   $f^{-1}(15) =$
2. What is $g^{-1}(13)\text{?}$
   $g^{-1}(13) =$