A:I’m afraid not
B:It’s up to you
C:That sounds good to me.
D:That depend
如图,已知矩形ABCD中,E、F分别为BC、AD上的点,将四边形ABEF沿直线EF折叠后,点B落在CD边上的点G处,点A的对应点为点H.再将折叠后的图形展开,连接BF、GF、BG,若BF⊥GF.
—Sorry to hear that. Who is taking care of him?
下列各组物质均属于硅酸盐工业产品的是( )