电力电容器在额定电流下运行,允许过载电流不得超过额定电流的1.3倍,以免发生().
A.爆炸;
B.放电;
C.热击穿;
D.触电.
参考答案:C
Mr More didn't feel ______ when he was ______. [ ]
A. lonely; alone
B. alone; lonely
C. lonely; lonely
D. alone; alone
对β2受体有选择性激动作用的平喘药是()
A.茶碱
B.肾上腺素
C.沙丁胺醇
D.色甘酸钠
E.异丙肾上腺素