How much dose it cost per pound?
To solve this problem you must apply the proccedure shown below:
1. You have that:
-The length is
feet.
- The width is
feet.
- The height is
feet.
2. The box has one base. The cost of the base is:

3. It has four sides. The cost of the sides are:

The answer is: The total cost is 
Hi
You should put into them.I mean
1-This is 2 part.First, you should put f(-1) then you should put what you found.
Solve is:f(-1)=3(-1)-2(-1)^2 so -3-2=-5 then put in other one:if f(-5):-15-50=-65
Is it correct?