Problem Description 

An underwater archway is being added to a large aquarium so that visitors can view the fish up close. The water in the aquarium will exert a tremendous force downward onto the transparent arch. This force needs to be calculated accurately so that a safe design can be developed.
What is known:
 The tunnel radius, a, of the glass arch is 9 ft.
 The water depth, b, is 20 ft.
 The length of the arch, L, is 30 ft.
 The water density ρ is 1.94 slug/ft^{3}.
