We are required to find the area of a circle to the nearest tenth
[tex]\text{Area of a circle = }\pi\times r^2[/tex][tex]\begin{gathered} \pi=3.14 \\ r=\text{ }\frac{diameter}{2} \\ \text{diameter = 1km} \\ r=\frac{1}{2}=\text{ 0.5km} \end{gathered}[/tex][tex]\begin{gathered} \text{Area of given circle via substitution hence =} \\ 3.14\times0.5^2=0.785km^2 \\ \text{Area of the circle hence}\approx0.8\operatorname{km}\text{ to the nearest tenth} \end{gathered}[/tex]Answer is option D
