First, we draw a picture
we must use pythagoras
![a^2+b^2=h^2](https://img.qammunity.org/2023/formulas/mathematics/college/8y42nfq1foypp0ooaxy3jwjni42acaxbz7.png)
where a and b are the sides of the triangle and h the hypotenuse
so, on this case the h is 20 because is the hypotenuse and 4 can be a or b, and the black line is the other side
then, replacing
![\begin{gathered} 4^2+b^2=20^2 \\ b^2=20^2-4^2 \\ b=\sqrt[]{20^2-4^2} \\ \\ b=8\sqrt[]{6}\approx19.5959 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/ijbot3kpa3jstgqbt6xxv5l85r6994s98r.png)
the distance is 19.5959 feet, so the right option is second