Answer:
perimeter of circle=2πr
16=2πr
r=16/2π=8/πcm
now.
area of circle=πr²=π(8/π)²=π×64/π²=64/(22/7)=64×7/22=20.36cm²
In order to solve this using V= B(h) (The B is area of the base) you need a radius it doesn't give us that but it does give us the circumference.
C= 3.14(2r)
25.12=2r divide each by 2
12.56=r
now use this in the volume formula:
V= 12.56^2(3.14)(66)
V=32,692.86 cubic inches
First we calculate the volume of the foundation:
Volume (V) = 20 ft * 12 ft * 4 in (1 ft / 12 in)
V = 80 ft^3
Since the cost is in cubic yard (yard^3) so convert:
V = 80 ft^3 * (1 yard^3 / 27 ft^3) = 2.963 yard^3
So the total cost is:
cost = ($125 / yard^3) * 2.963 yard^3
<span>cost = $370.37</span>
ANSWER

EXPLANATION
The area of the two tra-pezoidal faces

The area of the 5 by 6.4 rectangular face

The area of the two square faces

The area of the 9 by 5 rectangular face is

The surface area of the design is:
