（EMB145）如何得知CVR抹音成功？（）
A.可以听到一声800Hz的音频
B.可以听到持续3秒的300Hz的音频
C.状态灯亮3秒
参考答案：B
He went there and there for three days. [ ]
A. three days before; stay
B. for three days; stay
C. before three days; stayed
D. three days ago; stayed
经营企业销售人员销售无菌器械有哪些规定？
