根据色谱峰的个数，可以准确判断样品中所含组分的个数。
A. 对
B. 错
如果增大系统的开环增益,其奈奎斯特曲线与负实轴的交点的坐标和频率都会发生变化。
A. 对
B. 错
Our country has imposed a ban ____ smoking in public areas.
A. over
B. to
C. for
D. on
I walked all the way from office back home ____ necessity, 'coz I missed the only bus.
A. by
B. with
C. in
D. of
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