Answer:
40.565cm
Step-by-step explanation:
To find a circumference (perimeter) of a cirlce, you need to use the formula C=2πr.
We know the diameter is 8 but we need the radius, the radius we would divide the diameter in half.
8 ÷ 2 = 4
Now that we know the radius is 4, you plug in 4 for r, and then solve
C= 2π4
C= 25.13
The circumference of the whole circle is 25.13 so we would cut it in half to get the half of the circle we need. So 25.13 ÷ 2 = 12.565.
Now that we have the circumference of the half-circle, it a lot easier. Take the 3 other sides and the half-circle and just add the together
8 + 10 + 10 + 12.565 = 40.565