Answer:
49pi or about 153.94 square meters.
Explanation:
Because the two semicircles together take up the 28m long edge of the rectangle, they each half that diameter and a quarter of that radius. This means that both semicircles have a radius of 28/4=7. Since two semicircle with the same radius form a full circle, we can just calculate the area of a full circle of radius 7.
. Hope this helps!