A steel cylinder tank is 10 ft in diameter, 15 ft high, and is filled with a brine solution. Brine weighs 10 lbf/gal. The thickness of the steel shell is 1/2 in. The cylinder sits on a concrete pad 12ft x 12ft . What is the stress (a) at the bottom of the tank and (b) at the bottom of the concrete pad. (Concrete unit weight: 150 lb/ft3 , steel unit weight: 490 lb/ft3 , thickness of concrete pad is 1 ft)