It is not A or C, and D isn't specific enough (over what amount of time? is it flying up? down? It is going forward at the same height?) The most likely thing to stay consistent is the cost of fabric and it's length.
Say 1 foot of fabric is $3 (assuming there's no discount for additional feet, but math isn't that consistent with actual store sales), then 2 is $6, and 3 is $9. That is a constant rate of change.
Let h = height of the box,
x = side length of the base.
Volume of the box is

.
So

Surface area of a box is S = 2(Width • Length + Length • Height + Height • Width).
So surface area of the box is


The surface are is supposed to be the minimum. So we'll need to find the first derivative of the surface area function and set it to zero.

![4x = \frac{460}{ x^{2} } \\ 4x^{3} = 460 \\ x^{3} = 115 \\ x = \sqrt[3]{115} = 4.86](https://tex.z-dn.net/?f=%204x%20%3D%20%5Cfrac%7B460%7D%7B%20x%5E%7B2%7D%20%7D%20%20%5C%5C%20%204x%5E%7B3%7D%20%3D%20460%20%20%5C%5C%20x%5E%7B3%7D%20%3D%20115%20%20%5C%5C%20x%20%3D%20%20%5Csqrt%5B3%5D%7B115%7D%20%3D%204.86%20)
Then

So the box is 4.86 in. wide and 4.87 in. high.
Answer:
30.25 pi
Step-by-step explanation:
The circumference of a circle is given by
C = 2 * pi *r
11 pi = 2 * pi *r
divide each side by 2 pi
11/2 = 2 ( pi) * r/ ( 2pi)
11/2 = r
We can find the area by
A = pi * r^2
= pi ( 11/2) ^2
= pi ( 121/4)
= pi ( 121/4)
= 30.25 pi
First find out what 10 percent of 50 is
Do 50/10
I got 5
Then do 5 times 9 to get your answer
You should get 45. Thanks (: