Answer:
Felicia, these questions are tough for a lot of reasons, so it makes sense to me that nobody is giving you the right answers. here is a right one :)
Step-by-step explanation:
1st we need a strategy. brainstorm :P we are given the cost of material for boxes in area, we are asked how much 12 boxes would cost. let's find the area of the material for one box multiply that by the given cost. and then multiply that by 12 for the total cost. seem good? Yes there are other good ways to solve this problem if you're thinking that. this is just how I'm arbitrarily choosing to solve it.
1) surface area of prism box
1a) triangles on ends
1/2* b*p ( I think 6.2 is P for you, not positive about that)
1/2*6.4*6.2= 19.84
1b) flat sides
6.4*25 =160 ( this is B )
1c) add up the 5 sides
160*3 + 19.84 * 2 = 839.68 [tex]cm^{2}[/tex]
2) find the cost on 1 box
839.68 [tex]cm^{2}[/tex] * $0.0001 = 0.8397
about $0.84
3) find the cost for 12 boxes
0.8397 * 12 = 10.076
about $10.08
try those answers :)