防腐蚀工作成败的关键是对板件表面预处理的好坏。
参考答案：对
—May I use your dictionary? Mine is at home.
—______.[ ]
A. Thanks a lot
B. I'd love to
C. You're welcome
D. Sure. Here you are
在一个边长为12厘米的正方形纸板里剪出一个最大的圆，剩下的面积是______．
