Answer :
Area of the sea over which the ships are warned
= Area of the sector
(having \(r \ = \ 16.5 \) km and \(\theta \ = \ 80° \))
\( = \ \frac{ \theta }{360} \ × \ \pi r^2 \)
\( = \ \frac{80}{360}\ × \ 3.14 \ × \ (16.5)^2 \)
\( = \ \frac{68389.2}{360} \)
\(= \ 189.97 \) km2