21\,m\] The required
AREA
= 2\[\
TIMES
\]area of semi-circle EFA + area of rectangle ABDE \[=2\times \frac{1}{2}\pi {{(21)}^{2}}+80\times 42\] \[=\frac{
22
}{7}\times 21\times 21+80\times 42=4746\,{{m}^{2}}.\]