正弦交流电常用的表示方法是函数式、波形图和相量图。
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用三角函数可以表示正弦交流电最大值的变化规律。
A. 对
B. 错
简述电阻、电感和电容元件上的电流与电压数值及相位关系，并作出它们的电压与电流相量图。
1. She is tied to her smartphone she even uses to text a friend who lives one floor above her.
A. who
B. which;或不填
C. by which
D. where
Colleges began embracing Internet access in the mid -1990s, many began wiring dorms with high-speed connections.
A. where
B. when
C. which
D. that
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