the formula for a semi-circle is 3.14*d / 2 + the triangle
and d= 20 because the triangle is a equilateral so 3.14*20=62.8 and divide by 2 for it is the half of the circle 62.8 / 2 = 31.4 and add the triangle 31.4+40 because of the 2 sides 31.4+40=70.4
