Question

A. What is the approximate perimeter of the concrete region?

Answer 1

You have a square with half circles along the sides.
The length of each side is 4ft, so the radius of the circles is 2ft

to calculate the perimeter you can calculate the circumference of 4 half circles = 2 complete circles
c=2r*$\pi$=
2*2$\pi$=12.56
perimeter=2c=25.12=8$\pi$

the area is the area of 2 circles+the area of the square
circle area= r^2*$\pi$=2*2$\pi$=4$\pi$
concrete area=circle area*2+square area
=4$\pi$ *2+(4*4)
=8$\pi$+(4*4)
=8$\pi$+16ft
=41.12 ft^2