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【简答题】
passage 2.mp3 Passage 2 Spas are becoming more 1 _____ in the US. Last year, Americans visited spas a record of 2 _____ times, and spent about 3 _____ dollars. There are two trends in the spas. One trend: More American 4 _____ have been going to spas. Another trend: Spas are using more 5 _____, such as a 6 _____ ______headset for guided meditation. The whole idea is to be able to relax and make customers 7 _____.
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皮皮学刷刷变学霸
举一反三
【单选题】在 R 、 L 、 C 串联正弦交流电路中,若 XL < XC ,则总电压 u 与总电流 i 的相位关系为 ?
A.
u 超前于 i
B.
u 滞后于 i
C.
u 与 i 反相
D.
u 与 i 同相
【简答题】belong