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更多“Data received from two spacecr…”相关的问题
(A) Yes, they are very firm in their demands.
(B) Peter has placed an order for office supplies.
(C)They still need more time.
(14)
A．
B．
C．
听力原文：Mark! Haven't you received the fax from New York？
(A) No, not yet, Mrs. Frank.
(B) Thank you very much, Mrs. Frank.
(C) Yes, I haven't, Mrs. Frank.
(25)
A．
B．
C．
in a space level (i.e. the complement of a mark) for one element period. This element is called the start bit and has a duration of T seconds. The transmitter then sends the character, l bit at a time, by placing each successive bit on the line for a duration of T seconds, until all bits have been transmitted. Then a single parity bit is calculated by the transmitter and sent after the data bits. Finally, the transmitter sends a stop bit at a mark level (i.e. the same level as the idle state) for one or two bit periods. Now the transmitter may send another character whenever it wishes.
At the receiving end of an asynchronous serial data link, the receiver continually monitors the line looking for a start bit. Once the start bit has been detected, the receiver waits until the end of the start bit and then samples the next N bits at their centers, using a clock generated locally by the receiver. As each incoming bit is sampled, it is used to construct a new character. When the received character has been assembled, its parity is calculated and compared with the received parity bit following the character. If they are not equal, a parity error flag is set to indicate a transmission error.
(1).When the transmitter wishes to send data, it first sends().
A.a character at the same time
B.a character to the line
C.the start bit
D.a mark level to the line
(2).The transmitter then send the character, for a duration of T seconds().
A.each bit
B.all bits
C.successive bits
D.a start bit and a character
(3).Finally, the transmitter sends a stop bit at the same level as for one or two bit periods().
A.the space level
B.the mark level
C.the complement of the mark level
D.another character
(4).At the receiving end of an asynchronous serial data link, the receiver().
A.does not monitor the start bit
B.waits until the beginning of the start bit
C.samples the start bit at its center
D.generates a local clock
(5).When the received character has been assembled, its parity().
A.is set to indicate a transmission error
B.is compared with the received character
C.is an error flag
D.may be equal to the received parity
I ______letters from my daughter since she left.
A．don't receive
B．haven't received
C．didn't receive
M: I did，but she said she didn't know my size.
Q: What does the man mean？
(15)
A．He received a shirt from her aunt.
B．He expected his aunt give him a watch for Christmas.
C．He received a nice watch but he didn't like it.
D．He wanted a shirt but received a watch.
A．result in B．result from C．as a result of D．as a result
从下面提供的答案中选出应填入下列英文语句中______内的正确答案。
A local-area network(LAN) is a communications network that(1)a variety of device and provides a(2)for information exchange among those devices. The scope of the LAN is small typically a single building or a cluster ofbuildings. The LAN is usually owned by the same organization that owns the(3)devices. The internal data rate of LAN is at least several Mbps. The basic Of LAN communication is broadcasting. At each station, there is a transmitter/ receiver that communicates over a(4)shared by other stations.A transmission from any one station is(5)to and received by all other stations.
Which statement can NOT be inferred from the e-mail？
A．Liz Johnson has received letters from that company more than once.
B．The cargo can be delivered in Melbourne within two weeks.
C．The e-mail doesn't only enclose the details of the payment.
D．If the order is large enough they can talk about the discounts.
听力原文：Q: When will those specialists arrive from Wisconsin？
(A) Yes, we specialize in homepage customization.
(B) For about two weeks.
(C) I haven't received their itinerary.
(8)
A．
B．
C．
(22)
