The air pollution makes people ______bad. [ ]
A. feel
B. felt
C. to feel
D. feeling
A
把甲、乙两灯并联接在电源上,若甲、乙功率之比为2:1,则甲、乙两灯电阻之比为______;若将甲、乙两灯串联接在与上述相同的电源上,则甲、乙两灯消耗电功率之比为______.
老年失眠患者为降低跌倒风险,可选用的药物为()
A.地西泮
B.艾司唑仑
C.劳拉西泮
D.右佐匹克隆
E.阿普唑仑