4, 5 & 6 were answered on another question plus the circle isn't shown on this one.
7. semi circle is half a circle, there re 4 arcs smaller then half
they are DB, DC, AC and AB
last choice is correct
If it is a square all sides are equal, so the perimeter is equal to 4 times the length of one side...
4s=32
s=8in
Set up two seperate equations
first the volume equation
1728=length*width*height
we know the height is 6ft
1728=L*W*6
divide both sides by 6
288=L*W
then the second equation
L=4.5W
if one side is 4.5 times larger
then take that and plug it back into the first equation
288=(4.5W)*W
288=(4.5)w^2
divide both sides by 4.5
64=w^2
so w=8
then plug that back into the last equation
L=4.5(8)
L=36