Have you seen advertisements about hair care products? The models(模特) have shining hair like jewels(宝石). But now making hair shine is no longer the task of hair care products, because hair can be made into real jewels. Believe it or not, a company called LifeGem in the US makes it possible.

    The company is in the business of taking hair from dead people and making them into diamonds(钻石). Now the company plans to make three diamonds using Beethoven's hair to show their latest technology. The work will take about 7 months. In the end, Beethoven's long hair will become three shining diamonds.

    Since the great musician died in 1827, you may wonder where they got Beethoven's hair. A man called John Reznikoff gave the hair to the company. He holds the Guinness World Record for the latest and most valuable collection of celebrity(名人) hair. His collection also includes hair of Napoleon, Albert Einstein, Abraham Lincoln and John F. Kennedy. In total, the collection is worth over five million dollars.

    Though it sounds unbelievable, diamonds made with hair are for the families to remember the dead.

如图，Rt△ABC的两个锐角顶点A，B在函数y= $\frac{k}{x}$ （x>0）的图象上，AC//x轴，AC=2.若点A的坐标为（2,2），则点B的坐标为____.

已知椭圆M：：$\frac{x^2}{a^2}$+$\frac{y^2}{3}$=1（a＞0）的一个焦点为F（﹣1，0），左右顶点分别为A，B．经过点F的直线l与椭圆M交于C，D两点．

（Ⅰ）求椭圆方程；

（Ⅱ）当直线l的倾斜角为45°时，求线段CD的长；

（Ⅲ）记△ABD与△ABC的面积分别为S₁和S₂，求|S₁﹣S₂|的最大值．