A:
B:
C:
D:
分式方程32x=1x-1的解为( )
From his________look,I could see that he didn't believe what I said.
如图是光学显微镜的4个镜头,甲乙一端无螺纹,丙丁有螺纹.若要在视野内看到最多的细胞,宜选用的镜头组合是( )