A company is constructing an open-top, square-based, rectangular metal tank that will have a volume of 71.5 ft^3. What dimensions yield the minimum surface area? Round to the nearest tenth, if necessary. 6 ft by 6 ft by 2 ft 12 ft by 12 ft by 0.5 ft 5.2 ft by 5.2 ft by 2.6 ft 4.2 ft by 4.2 ft by 4.2 ft