若（a+1）²+|2﹣b|=0，则b^a的值为（　　）

阅读理解

　  Tim and Li Fang are not going to have any classes next week. They're going to work on a farm.

      They are going to leave at about seven thirty on Monday morning. They are going to travel to the farm by bus. They are going to wear old clothes because they are going to grow rice. They are going to have fish for lunch. They are also going to have a swim at the farm.

     Tim and Li Fang are excited about going to the farm. Not only are they going to help around the farm, but also they are going to learn about farming.

      Li Fang is worried that Tim won't arrive on time to catch the bus because he is nearly always late. Li Fang often has to say to him, “Don't be late, Tim. ”

阿基米德原理：浸在液体中的物体所受到的浮力，大小等于物体排开液体所受到的重力．即F_浮=G_排=ρ_液gV_排．．浮力产生的原因是液体对物体上下表面产生的压力差．即F_浮=F₂﹣F₁．

如图所示，在研究浮力是如何产生的问题时，设想有一个底面积为S，高为h的长方体物块浸没在水中，由于水对长方体上表面的压力F₁和下表面的压力F₂不同，从而产生了对物块的浮力．请利用浮力产生的原因推导出：F_浮=ρ_液gV_排．