属于IC类抗心律失常药物是()
A.普鲁卡因胺
B.美西律
C.普罗帕酮
D.苯妥英钠
E.利多卡因
参考答案:C
—Could you tell me _____?
—Yes. He _____ to Australia. [ ]
A. where is he; has gone
B. where he is; has gone
C. where he is; has been
如图表示某双缝干涉的实验装置,当用波长为0.4μm的紫光做实验时,由于像屏大小有限,屏上除中央亮条纹外,两侧只看到各有3条亮条纹,若换用波长为0.6μm的橙光做实验,那么该像屏上除中央条纹外,两侧各有几条亮条纹?