The diameter of a circular aquarium is 64 meters, and there is a circular island in the middle. The radius of the island is 5 meters. How many square meters is the water area of this aquarium?
一个圆形养鱼池的直径是64米，中间有一个圆形小岛，小岛半径是5米，这个养鱼池的水域面积是多少平方米？
<result>3_136.36</result>