【单选题】We walked a long way to see him off, only _____ that he had just left.
【单选题】—_____ does your English teacher teach you English songs? —Once a week. [ ]
【判断题】因感抗与频率成正比,故电感具有“通直流、阻交流” 和“通低频、阻高频”的作用。
【简答题】为什么电感具有“通直流、阻交流”的作用?
【单选题】某患者,男性,43岁。被诊断为抑郁症,长期口服丙咪嗪进行治疗,一次患者超剂量服用丙咪嗪后,急查血药浓度以确定患者是否中毒。丙咪嗪的致死血药浓度为大于