16. Find the surface area of the funnel

A 21 $cm$ lengthy funnel is in the form of a frustum surmounted on a cylinder. The base radius of the cylinder is 2 $cm$ and the height of the frustum is $6.3$ $cm$. If the top radius of the funnel is 4 $cm$, then find the outer surface area of the funnel.

 

Answer:

 

The outer surface area of the funnel $=$  $cm^2$

 

[Note: Enter the answer up to two decimal  places.]