Possible dimension of a box with a volume of 100 cubic cm
10 x 10 x 1 = 100
10 x 5 x 2 = 100
5 x 5 x 4 = 100
Surface area:
10 x 10 x 1 dimensions:
10 x 10 = 100 x 2 = 200 sq.cm
10 x 1 = 10 x 4 = 40 sq. cm
240 sq. cm * $0.05 / 100 sq.cm = $0.12 per box
0.12 per box * 100 boxes = $12
10 x 5 x 2 dimension
10 x 5 = 50 x 2 = 100 sq. cm
10 x 2 = 20 x 2 = 40 sq. cm
5 x 2 = 10 x 2 = 20 sq. cm
160 sq. cm * $0.05/100 sq. cm = $0. 08 per box
0.08 per box * 100 boxes = $8
5 x 5 x 4 dimension
5 x 5 = 25 x 2 = 50 sq. cm
5 x 4 = 20 x 4 = 80 sq. cm
130 sq. cm * $0.05/100 sq. cm = $0.065 per box
0.065 per box * 100 boxes = $6.50
The best dimension to use to have the least cost to make 100 boxes is 5 x 5 x 4. It only costs $6.50 to make 100 boxes.
a)
his income must be "x" which is the 100%, and we would know that 0.2% of that is 12.37.

b)
his income must be "x" which is the 100%, and we would know that 2% of that is 12.37.

btw he's not making much either way.
We know that the Circumcenter is the intersection of a triangle's right (perpendicular) bisectors. Once you have found two of these you can determine their point of intersection.
It is a proven mathematical concept that the third perpendicular bisector will also cross through this intersection point. While it is not necessary to construct all three it is often done so to verify that the intersection of the first two perpendicular bisectors was in fact correct.
It is C, "What type of paper are most greeting cards made with."