looking at your picture, you have 1 rectangles with 2 semicircles attached to the side.
The rectangle has dimensions of 8m by 10 m and the semicircle has a diameter of 10
now, the area of a rectangle is A=b*h
where A- area
b- base = 8m
h-height= 10m
the area of a circle is

and a semicircle is just one half the area of a circle, so

but you have two semicircles, so you can just add the area of a circle to the area of the rectangle to get the total area
now, the diameter is 10m, which means that teh radius of a circle is 5m


