征收进口附加税的目的主要有（）

A.增加财政收入

B.维持进出口平衡

C.应付国际收支危机

D.防止外国商品低价倾销

E.对他国实行歧视或报复

When the system upon which a transport entity is running fails and subsequently restarts, the (136) 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 problem.
The still active side of a half-open connections can close the connection using a (137) timer. This timer measures the time the transport machine will continue to await an (138) of a transmitted segment after the segment has been retransmitted the maximum number of times. When the timer (139) , 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 restarts, half-open connections can be terminated more quickly by the use of the RST segment, the failed side returns an RST i to every segment i that it receives, when the RST i reaches the other side, it must be checked for validity based on the (140) 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．data

B．state

C．signal

D．control