某城市拟建一座水泥厂，该市的常年主导风向为东南风，根据城市规划卫生学要求，该水泥厂宜建在城市的
A．西南
B．南
C．东南
D．东北
E．西北
参考答案：E
若A（m，5）与B（-6，-n）关于x轴对称，则（m+n）2011=______．
—Why does the lake smell terrible?
—Because large quantities of water_______________.
A．have polluted
B．is being polluted
C．has been polluted
D．have been polluted
