Answer:
D
Step-by-step explanation:
40 / 2 = 20
area = (pi)*r*r
20*20*(PI) = circle area
it's half of the area, so you need to divide it by 2
b
I just did it in my math class and got it right
4
you would divide -20 / -5 = 4
it's D, 6.6 in.
height= 2 area/base
h= 2(39.6)/12
≈6.6 in.