我国有权修改宪法的机关是()。A．全国人大 B．全国人大常委会 C．全国人大及其常委

某化肥包装袋上的部分说明如图所示．

（1）硝酸铵属化学肥料中的______（填序号）：

A．钾肥                B．氮肥                  C．磷肥

（2）硝酸铵应具有的性质是______（填序号）：

A．易溶于水             B．有挥发性         C．受热易分解

（3）硝酸铵能与强碱反应，其中与烧碱反应的方程式为：NH₄NO₃+NaOH=NaNO₃+NH₃↑+X，则X的化学式是：______；施用该类肥料时，要避免与______（填“酸”或“碱”）性物质混用，否则会减低肥效．

清创术的延期缝合是（）。
清创术的早二期缝合是（）。
清创术的晚二期缝合是（）。

A.术后1～2天，创面清洁，肉芽健康，渗液少

B.术后4～7天，创面清洁，肉芽健康，渗液少

C.术后8～14天，感染控制，创面清洁，肉芽健康，渗液少

D.术后超过14天，感染控制，使老化伤口转变为新鲜伤口

E.术后超过20天，感染控制，创面缩小

解热镇痛药的镇痛作用机制是( )。

A．阻断传入神经的冲动传导

B．降低感觉纤维感受器的敏感性

C．阻止炎症时PG的合成

D．激动阿片受体

E．抑制抑黄嘌呤氧化酶

癃闭的病位是在膀胱，但和三焦、肺、脾、肾、肝均有着密切的关系。

We have already covered the topic of network addresses. The first  (1) in a block (in classes A, B, and C) defines the network address. In classes A, B, and C,if the hostid is all ls,the address is called a direct broadcast address. It is used by a(2) to send a packet to all hosts in a specific network. All hosts will accept a packet having this type of destination address. Note that this address can be used only as a (3) address in an IP packet. Note also that this special address also reduces the number of available hostid for each netid in classes A,B，and C． In classes A, B, and C, an address with all ls for the netid and hostid (32bits) define a (4) address in the current network.A host that wants to send a message to every other host can use this address as a destination address in an IP packet. However, a router will block a packet having this type of address to confine the broadcasting to the (5) network. Note that this address belongs to class E.

空白（4）处应选择（）

A.unicast

B.multicast

C.broadcast

D.anycast