体视显微镜是使用(),经棱镜将像会聚在(),用双目镜观察,便可获得()的显微镜。
参考答案:两个相对的物镜成像;同一焦平面上;三维立体像
Since then the number of people who were addicted to smoking ________ 20%.[ ]
A.has reduced to
B.reduces by
C.has reduced by
D.have reduced by
人差方程式