25. An innovative landscaper plans to design a rectangular garden adjacent to a riverbank. The landscaper intends to use the river as one side of the garden and expensive ornamental fencing for the other three sides. Given 100 meters of ornamental fencing, determine the dimensions that would create a garden of maximum area. Additionally, the landscaper wants to install a decorative fountain in the center of the garden, reducing the available space. The fountain has a circular base with a radius of 5 meters. How should the garden be designed to maximize the remaining area after considering the fountain? What is the maximum remaining area?