单项选择题

It is believed that a new technique to ______ will probably be found.

A．recycle old aluminum products
B．discover more bauxite ores
C．make aluminum by putting ore particles under water
D．take out aluminum magnetically from poorer ores

<上一题目录下一题>

热门试题

单项选择题

In the second paragraph the word paramagnetic means ______.

A．slightly magnetic
B．a weak magnetic field
C．a strong magnetic substance
D．the under-water magnetic power

单项选择题

According to the announcement which of the following is true of special summer hours for the library

A．It has them only on the weekends.
B．It has them both weekdays and weekends.
C．It has no special summer hours.
D．The information is not availabl