I need help with 1 and 2

1 ) A rancher plans to make four identical and adjacent rectangular pens against a barn, each with an area of 100 m2. What are dimensions of each pen that will minimize the amount of fence that must be used? 2) Suppose an airline policy states that all baggage must be box-shaped with a sum of the length, width and height not exceeding 108 in. What are the dimensions and volume of a square-based box with the greatest volume under these conditions