用纯水洗涤玻璃仪器时，使其既干净又节约用水的方法原则是少量多次。
参考答案：对
After ten years of living in a remote village, she is a completely different person from _____
she used to be.
A．that
B．whom
C．what
D．who
测量直流电压常用（）电压表。
A.磁电式
B.电磁式
C.整流式
D.电动式
