Hello nice to meet everyone this is my first post, I'm in need of help badly, regarding 2 precalc questions

Hello,

I have a math hand in due for class this evening around 5pm. There are several questions on this handout relating to trig and calc but these two problems I'm having trouble setting up the correct formulas and even creating the correct formulas to finish off the problem. Below are the copied and pasted questions, there were no diagrams given with the questions us our class to help, sorry.

Any help would be very much appreciated, thanks.

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2) An open box is to be made from a rectangular piece of cardboard having dimensions 20 inches by 30 inches by removing squares of area x2 from each corner and turning up the sides.

a) Show that there are two boxes that have a volume of 1000 cubic inches. Give their dimensions.

b) Which box has the smaller surface area?

3) A man wishes to put a fence around a rectangular field and then subdivide the field into three smaller rectangular plots by placing two fences parallel to one of the sides. If he can afford only 1000 yards of fencing, what dimensions will give the maximum rectangular area?

a) Express y as a function of the length x.

b) Express the total enclosed area A of the field as a function of x.

c) Find the dimensions that maximize the total enclosed area.