21. Find the total surface area of the remaining solid

From a solid cylinder whose height is 4 \(cm\) and diameter 6 \(cm\), a conical cavity of the same height and base is hollowed. Find the total surface area of the remaining solid.

 

The total surface area of the remaining solid \(=\)  \(cm^2\)

 

[Note: Round off your answer up to one decimal place.]