Hello there!
Your answer is D) not justifiable, because there is another variable to consider.
While Susie may gain weight during Christmas, the holiday is not magically making her gain weight. It is more likely all of those candy canes.
I hope I helped!
Let me know if you need anything else!
~ Zoe
First question
42 students
Second question 65%
Let
x---------> the length side of the rectangular area
y---------> the width side of the rectangular area
we know that
the area of the rectangle is equal to

-----> equation 
The perimeter of the rectangle is equal to

but remember that the fourth side of the rectangle will be formed by a portion of the barn wall
so
-----> equation 
<em>To minimize the cost we must minimize the perimeter</em>
Substitute the equation
in the equation 
![P=x+2*[\frac{200}{x} ]](https://tex.z-dn.net/?f=%20P%3Dx%2B2%2A%5B%5Cfrac%7B200%7D%7Bx%7D%20%20%5D%20)
Using a graph tool
see the attached figure
The minimum of the graph is the point 
that means for 
the perimeter is a minimum and equal to 
<u>Find the value of y</u>



The cost of fencing is equal to

therefore
<u>the answer is</u>
the length side of the the fourth wall will be 
Let
be the length and
be the width of the rectangle.
Given perimeter of the rectangle

Area of the rectangle is

Also length is 5 more than twice its width,

From the above equations

Now 
The dimensions of the rectangle are length
, and width
.
A^2 + b^2 = c^2
9^2 + b^2 = 15^2
81 + b^2 = 225
225 - 81 = b^2
144 = b^2
square root of 144 = 12
b = 12