为了改善市民的生活环境,我市在某河滨空地处修建一个如图所示的休闲文化广场．在Rt△ABC内修建矩形水池DEFG,使顶点D、E在斜边AB上,F、G分别在直角边BC、AC上;又分别以AB、BC、AC为直径作半圆,它们交出两弯新月（图中阴影部分）,两弯新月部分栽植花草;其余空地铺设地砖．其中AB=24$\sqrt{3}$米,$\angle BAC=60°$．设EF=x米,DE=y米．

（1）求Y与x之间的函数解析式;
（2）当X为何值时,矩形的面积最大?最大面积是多少?
（3）求两弯新月（图中阴影部分）的面积,并求当X为何值时,矩形的面积等于两弯新月面积的$\frac{1}{3}$?

    2014 is the year of horse in China. Do you know anything about the horse?

    The horse is strong and runs very fast. He's a useful and hard-working animal. The horse learns to know his owner soon. He loves his owner, even after his owner loses his life. Here's a story about such a horse. In a war, the owner passed away(死), and fell from his horse. When people found his body some days later, the horse was still standing beside it. During that long time, the horse didn't leave the body of his owner, without food or water, in the coldest weather, driving away the birds that might eat it. Wasn't he a great animal?

换偏旁，变新字。

绊——____ ____   蓝——____ ____