Answer:
Option D [tex]549\ km^{2}[/tex]
Step-by-step explanation:
we know that
The surface area of the figure is equal to
[tex]SA=2B+Ph[/tex]
where
B is the area of the base
P is the perimeter of the base
h is the height of the figure
so
Find the area of the base B
The area of the base is equal to the area of five isosceles triangle
[tex]B=(5)*(\frac{1}{2}*9*6.2)=139.5\ km^{2}[/tex]
Find the perimeter of the base P
[tex]P=9*5=45\ km[/tex]
[tex]h=6\ km[/tex]
substitute
[tex]SA=2*(139.5)+45*6=549\ km^{2}[/tex]
