Answer: Choice A
40.61 square meters
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Step-by-step explanation:
The area of a full circle is
A = pi*r^2
meaning half of it (aka semicircle) will have this area
A = 0.5*pi*r^2
The diameter of the semicircle is 5.4 meters, which divides in half to get the radius of r = 2.7
The semicircle has an area of...
A = 0.5*pi*r^2
A = 0.5*3.14*(2.7)^2
A = 11.4453
which is approximate since pi = 3.14 is approximate.
Now compute the area of the triangle
area = base*height/2 = 5.4*10.8/2 = 29.16
Then add those sub-areas to get the grand total area.
semicircleArea + triangleArea = 11.4453+29.16 = 40.6053
That rounds to 40.61 which shows why choice A is the answer.