在小儿下呼吸道解剖组织特点中,以下哪项是错误的()
A. 气管和支气管腔相对狭窄,黏膜血管丰富
B. 黏膜纤毛运动差,不能很好地排出微生物
C. 肺脏弹力组织发育差,血管丰富
D. 肺泡数量少,含气量相对较少
E. 喉呈漏斗状,喉腔狭窄
查看答案
钴-钼催化剂加氢气脱硫生成硫化氢,能除掉原料中的非反应性硫、氢气的加入量一般占原料体积()。
Your network contains an Active Directory domain. The domain contains two domain controllers named DC1 and DC2. DC1 hosts a standard primary DNS zone for the domain. Dynamic updates are enabled on the zone. DC2 hosts a standard secondary DNS zone for the domain. You need to configure DNS to allow only secure dynamic updates. What should you do first()
A. On DC1 and DC2, configure a trust anchor.
B. On DC1 and DC2, configure a connection security rule.
C. On DC1, configure the zone transfer settings.
D. On DC1, configure the zone to be stored in Active Directory.
函数()算出返回记录的行数。
A. count
B. min
C. avg
D. num