Since risk is associated with most projects,the best course of action is to (71)A.cover al

● A glue that holds the whole Internet together is the network layer protocol,(71). Unlike most older network layer protocols, it was designed from the beginning with internetworking in mind. Its job is to provide a -(72) way to transport datagrams from source to destination, without regard to whether these machines are on the same network or whether there are other networks in between them.

Communication in the Internet works as follows. The (73)layer takes data streams and breaks them up into datagrams. Each datagram is transmitted through the Internet, possibly being fragmented into smaller units as it goes. When all the pieces finally get to the destination machine, they are reassembled by the

(74) layer into the original datagram. This datagram is then handed to the transport layer, which inserts it into the receiving process' input stream.

An IP datagram consists of a header part and a text part. The header has a (75) part and a variable length optional part.

(71) A. IP (Internet Protocol)

B. IP (Interworking Protocol)

C. TCP (Transport Control Protocol)

D. TCP (Transfer Communication Protocol)

(72) A. best-quality

B. quality-guaranteed

C. connection-oriented

D. best-efforts

(73) A. data link

B. transport

C. network

D. application

(74) A. data link

B. transport

C. network

D. application

(75) A. 40-byte fixed

B. 64-byte fixed

C. 20~64 bytes variable

D. 20-byte fixed

A briefing is a short presentation usually given at a meeting or a conference to bring people up to date on business activities , projects , programs or procedures.

—Which subject do you like______?

—I like chemistry than any other one.

A. better, better

B. best, better

C. best, best

D. better, best

___________

A. presented B. marked C. lit D. associated

[ A] introduced

[ B] persuaded

[ C] associated

[ D] stimulated

A healthy life is frequently thought to be _______ with the open countryside and homegrown food.

A) tied B) bound

C) involved D) associated

Electronic mail and filing permit a user to compose and transmit a message on an office(71)system. In the early 1970s, the ARPANET community developed a number of such systems which have been heavily used. Through standard message format(72), several hundred different computers and electronic mail interfaces are specification of how(73)and return addresses should appear on envelopes and which sizes are allowable for envelopes. In the electronic message world, they describe what(74)of characters are required at the(75)of a message to identify the sending and receiving mailboxes.

A．robotization

B．automation

C．dynamic

D．action