It may be concluded that testing（）
A. should deal with only opinions
B. should always be written
C. has changed since the Middle Ages
D. is given only in factories
当用电负荷允许中断供电时间要求在( )以内时，应用不间断电源UPS。
A. 0.1s
B. 1s
C. 1.5s
D. 2s
It is much easier to talk about social change than to ______.
A. bring it down
B. bring it out
C. bring it up
D. bring it about
69（）
A. come from
B. result in
C. succeed in
D. depend on
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