5544m2
1386m2
132m2
264m2
693m2
Correct answer is E
\(\pi\) = \(\frac{22}{7}\), Diameter D = 42m
Area of a circle = \(\frac{\pi D^2}{4}\) when a diameter is given
area of a semicircle \(\frac{\pi D^2}{4}\) x \(\frac{1}{2}\)
= \(\frac{22}{7}\) x \(\frac{4262}{4}\) x \(\frac{1}{2}\)
= \(\frac{11}{7} \times 441\)
= 693m\(^{2}\)