The height, bigger radius, and smaller radius in a frustum of a right circular cone is given by h, R, and r respectively. Which of the given relation would give us the slant height of the frustum of a right cone.
1
\(\sqrt{R^2 + r^2 +h^2}\)
2
\(\sqrt{(R-r)+h^2}\)
3
\(\sqrt{(R+r)^2+h^2}\)
4
\(\sqrt{(R-r)^2+h^2}\)