2017 Cayley Problem 3

A snowman is built by stacking three spheres with their centres aligned vertically. The spheres have radii of 10 cm, 20 cm and 30 cm. How tall is the snowman?

\textbf{(A)}\ 90 \text{ cm}\quad \textbf{(B)}\ 100 \text{ cm}\quad \textbf{(C)}\ 110 \text{ cm}\quad \textbf{(D)}\ 120 \text{ cm}\quad \textbf{(E)}\ 130 \text{ cm}

If there are no answer choices shown, enter a numerical answer.

Full credit to this problem is given to the CEMC, you may view all Cayley contests here.