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.]