You want to build a field next to your barn in the shape of a trapezoid. Three sides of the trapezoid have equal length (see diagram): AB=BC=CD. The three sides of equal length will be built using a total of 30 meters of fencing, while the barn forms the fourth side. Find the largest possible area of the field. Make sure you clearly define your variables, and provide a clear final answer in words, which includes the appropriate units. B r-------------------------sC I \\ ; Field \\ Barn (Note: You may assume that the barn is at least 30 meters long.)