题目3A. 开路B. 电阻C. 短路<img src="https://tihai-oss-cloud.itihey.com/img/efe3de4e7e19e9c2715ff4e1653fccdc.jpg"><img src="https://tihai-oss-cloud.itihey.com/img/d8a6428329908437d3f11ddc7062105c.jpg">4、已知正弦电压 , , ,则超前<img src="https://tihai-oss-cloud.itihey.com/img/f3f7b63a0b9354b6f948758b46b4405b.png">.( C)A.-90°B.210°C.-150°D.-120°