一台显微镜有5X,10X,15X三个目镜,有10X,45X两个物镜,这台显微镜的最低放大倍数和最高放大倍数分别是( )
A:50倍、250倍
B:100倍、450倍
C:50倍、675倍
D:150倍、675倍
适用于我国县乡人大代表的选举方式是( )
You can take anything from the shelf and read, but please ________ the books when you've finished with them.