表17-6是该系统中路由器的IP地址分配表。 表17-6 IP地址分配表 路由

观察实验装置，回答下列问题：

（1）左图是某学生设计的一种有洗气、贮气等用途的装置。氢气是难溶于水，密度比空气的密度小的气体，当用排水集气法收集氢气时，瓶内先装满水，气体从________ (填“a”或“b”，下同)处导管通入；若要用水将瓶中氢气排出使用，水应从_______处导管进入。若用排空气法收集氧气时，瓶内先装满空气，氧气从_______处导管通入。

（2）右图为可用推拉注射器活塞的方法检查图中装置的气密性。当缓慢向右拉活塞时，如果装置气密性良好，可观察到_______________。

男，16岁，胸骨左缘3、4肋间闻及响亮的收缩期杂音，震耳，伴有震颤，但听诊器离开胸壁听不到。

该杂音为（）.

A.1／6级杂音

B.2／6级杂音

C.3／6级杂音

D.4／6级杂音

E.5／6级杂音

下列建筑物、构筑物边不宜种灌木的有（）。

A.公路铺筑面外侧

B.道路侧石线（人行道外缘）

C.挡土墙基

D.天桥边缘

E.路牌、交通指示牌、车站标志

按萃取剂与被萃元素的络和方式来划分萃取剂大致可划分（）。

A.中型络合萃取剂

B.阳离子萃取剂

C.阴离子萃取剂

D.螯合萃取剂

B Egyptian Villages 埃及村落

Most of the inhabitants live in mud-brick homes, their (1)  walls insulating against the afternoon heat. Flat roofs, exposed (2)  the northern evening breezes, serve as cool sleeping (3)  as well as storage areas. Villagers plaster the outer walls (4)  often trim them in blue, a color they believe (5)  off the evil eye. As a man becomes richer, (6)  can add a second story to his house perhaps (7)  his married son. Those villagers who have made the (8)  to Mecca paint the legend of their trip on (9)  outer walls of their homes. Such hajj houses, along (10)  the mosques, are the most distinguished buildings in a (11)

Some villagers build ornate pigeon coops close to their (12) , using the birds as food and their droppings to (13)  crops. Many houses still have dirt floors and lack (14)  or running water; women with jars balanced on their (15)  make the trek to the community well, and children donkeys haul the (16)  liquid in jerry cans.

All (17)  said, government sponsored building programs have also brought newer (18)  residences and utilities to some villages, particularly those outside (19)  Nile Valley in the Oases and the Red Sea (20)  areas.

1.（）