Calculate the square footage and the roof and wall area of a building with a circular segment shaped roof.
Square footage of the building is calculated as length times the width of the building.
The gable walls are considered to be full gable walls so it includes the wall and roof segment heights.
The roof area in square feet is calculate by multiplying the arc length by the length of the building.
It also calculates the radius of the circle the circular segment shape is based on.