A prize winning animal is going to be shown at the State Fair. A pen must be constructed to hold the animal.

The rectangular pen will have three wooden sides, which cost 25 dollars per foot to construct. The front of the pen will be made of a special reinforced glass, which costs 55 dollars per foot to construct.

The animal requires an area of 70 square feet in order to be comfortable.

If the pen is to be built as cheaply as possible, what are the dimensions of the pen that should be built?

Length of glass front of pen : (in feet)

Depth of pen? (in feet)

How much will the pen cost to build?

Cost of pen : (in dollars)

A manufacturer wants to design an open-top box having a square base and a surface area of 90 square inches.

What dimensions will provide a box with maximum volume?

Length of base :inches

Width of base :inches

Height of box :inches

Give all of your answers correct to two decimal places.