问题 单项选择题

When the system upon which a transport entity is running fails and subsequently reatarts, the ______ information of all active connections is lost. The affected connections become half-open, as the side that did not fail does not yet realize the promble.
The still active side of a half-open connections using a ______ timer. This timermeasures the time transport machine will continue to await an ______ of a transmitted segment after the segment has been retransmitted the maximum number of times. When the timer ______, the transport entity assumes that either the other transport entity or the intervening network has failed. As a result, the timer closes the connection, and signals an abnormal close to the TS user.
In the event that a transport entity fails and quickly restart, half-open connections can be teminated more quickly by the use of the RST segment. The failed side returns an RSTi to every segment i that it receives. When the RSTi reaches the other side, it must be checked for validity dased on the ______ number i, as the RST could be in response to an old segment .If the reset is valid, the transport entity performs an abnormal termination.

A. abandon B. give-up C. quit D. connection

答案

参考答案:B

阅读理解

阅读理解

     When they go to the new supermarket, all the housewives(家庭主妇)have one great wish:to be the lucky customer

so that they needn't pay for their shopping. Mrs. Edward hopes, like many of her friends, to be the lucky customer.

Unlike her friends, she never gives up. The cupboards in her kitchen are full of things which she doesn't need. Her

husband persuades(劝说)her to stopping buying things mat she doesn't need., but it is of no use. She dreams that

her lucky day is coming.

     One Friday afternoon, after she finishes her shopping and is taking the things to her car, she finds that she forgot

to buy some tea. She goes back to the supermarket, gets the tea and goes to the cashier(收银台).She sees the manager

come up to her."Madam,"he says,holding out his hand,"I want to congratulate you! You are our lucky customer and

everything you have in your basket is free."

1.The customer in the supermarket _______.

A. wants to go around the supermarket  

B. doesn't have to pay for shopping

C. wishes to know what to buy

D. could get free things if she/he is lucky

2.Mrs. Edward's husband _______things which she is not in need of.

A. likes her wife buying

B. enjoys her being the lucky customer

C. can't stop her from buying

D. would like her to buy

3.Mrs. Edward gets her free things _______.

A. on Sundays

B. in the evening

C. on Friday

D. with her husband

4.Mrs. Edward feels a little _______although she was the lucky one finally.

A. happy

B. sorry

C. angry

D. surprised

5.The main purpose of the passage is to tell us not to _______.

A. do shopping at a new supermarket

B. go back to the supermarket after you leave it

C. go shopping on Friday, because some people think it is an unlucky day

D. dream of getting lots of things for free at any shop

单项选择题