You may borrow the book ______ you keep it clean（）
A. as long as
B. when
C. after
D. unless
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把RNA转移到硝酸纤维素膜上的技术叫（）
A. Southern blotting
B. Northern blotting
C. Western blotting
D. Eastern blotting
Which of the following biasing combinations is not normally associated with one of the three transistor operating regions（）
A. E-B junction = forward, C-B junction = reverse
B. E-B junction = reverse, C-B junction = reverse
C. E-B junction = reverse, C-B junction = forward
D. All of the above
VCE is measured ______（）
A. from the emitter terminal to ground
B. from the collector terminal to the emitter terminal
C. from the collector-emitter junction to ground
D. None of the above
In the saturation region, the base-emitter junction _____（）
A. and the base-collector junctions are both forward-biased
B. and the base-collector junctions are both reverse-biased
C. is forward-biased while the base-collector junction is reversed-biased
D. is reversed-biased while the base-collector junction is forward-biased
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