diameter = 4 x 2 = 8
the area of a circle = pi x r^2 = pi x 8^2 = pi x 64 = 64pi
divide 64pi by two to get the area of the semicircle which is 32pi
area of one of the triangles = 4x4=16/2=8
three circles = 8x3=24
area of shaded = 32pi - 24
32pi = 100.53
100.53-24=76.53