比例尺的计算公式是：比例尺=_______________。

根据短文内容，判断句子的正（T）误（F）。

     James wrote a play for television about a family who came to England from India, and the play was

very interesting. It was bought by an American TV company.

     James was then invited to go to New York to help them. He lived in Washington, which is an hour

away from New York by air. The plane was going to take off at 8:30 in the morning. So he had to be

at the airport at about 7:30. He ordered a taxi for 6 :30 and went to sleep. He forgot to wind (土条)

the clock, and it stopped after midnight. Also the driver of the taxi had to work very late that night and

he got up very late the next morning.

     James woke with the feeling that something was wrong. He looked at his clock. It stood there silently

with the hands pointing to ten past twelve. He turned on the radio and knew it was ten. He was late for

the plane.

     He was just preparing his coffee when the radio sent out another news, ''Reports are coming in of a

plane crash (飞机坠落) near Washington airport. A Boeing 707 fly to New York crashed shortly after 

taking off this morning. Plane  number  2234…"

     James suddenly turned pale (苍白).

     "My plane,"  he said aloud.   "If I haven't been late,  I'd have been on the plane!"

( )1. James was a writer from England.

(     )2. He had to reach the airport at half past eight.

(     )3. James would like to take a taxi at six thirty.

(     )4. When he turned on the radio he heard the speaker saying that he missed the plane.

(     )5. James was lucky because he was not able to get on the plane.

1岁小儿腹泻，重度脱水伴重度酸中毒，此患儿需累计损失的液量及首次补充的5%碳酸氢钠的量分别约是

A．600mml 25mml

B．800 mml 35mml

C．1000mml45 mml

D．1200mml55 mml

E．1400mml 65mml

产生于战国中期的诸子散文是______

A．《论语》
B．《墨子》
C．《孟子》
D．《荀子》

企业能够实现利润的情况是（）

A.边际贡献小于固定成本

B.边际贡献大于固定成本

C.边际贡献小于变动成本

D.边际贡献大于变动成本

ISDN的接口可以是PRI或BRI。ISDN的信道有两种类型：B和D。B信道主要是用来运送数据的工具，每个B信道拥有最大可达64kb/s的吞吐量，主要用于电路交换的数据通信，也可用于基于包交换的数据通信。D信道用来传输请求ISDN交换的信令。实际上， D信道提供一个到电信提供商中心局的本地回答，也可用于传送基于包交换的数据(如 X.25)。BRI是最典型的ISDN连接，并且是路由器上的一个本地ISDN接口，基本带宽是 2B+D。

在ISDN的BRI安装中，NT1(NT2)是一个重要的小设备，NT1类似于串行连接中用到的CSU/DSU，它是终接本地回路的设备(其实NT1就是一个将电话2线变4线的设备)。NT1至少有2个接口：一个S/T接口和一个U接口。S/T接口连到路由器的BRI接口上；U接口连接到ISP提供的插座上。许多具有BRI功能的Cisco路由器都有一个集成的NT1接口。这些接口都有一个BRIU标签，如果底板上没有这个特性，则接口会标BRIS/T，从而需要一个外部的NT1。这个本地的ISDN接口就是路由器的TE1接口。TE1终端适配卡专用于连接ISDN。

以下是路由器部分的配置清单：

Router(config)# ISDN switch-type basic-5ess

Router(config)# interface BRI0

Router(config-if)# ip add 192.168.10.1 255.255.255.0

Router(config-if)# encapsulation PPP

Router(config-if)# dialer idle-time out 1 80

Router(config-if)# dialer mapip 192.168.10.2 07314433018 (1)

Router(config-if)# dialer-group1

Router(config)# dialer-list protocol ip permit

【问题3】如果ISDN收费是按每分钟计算，假如0.5元/分钟，采用ISDN基本速率接口下载1024k的文件需要付费多少？