A:剪纸
B:用铁矿石炼钢生产“扬州三把刀”
C:用玉石加工成精美“扬州玉”
D:将宝石镶嵌在胚体上制作扬州漆器
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用配方法解方程x2-2x=2,原方程可变形为( )
当晨昏圈与经线圈重合时,下列说法正确的是( )