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问题 选择题

今年春节期间我市燃放烟花爆竹的数量明显减少，这有效控制了空气中何种有害气体的增加？（　　）

A．氮气

B．二氧化硫

C．氢气

D．稀有气体

答案

A、燃放烟花爆竹不会产生氮气．故A不符合题意；

B、燃放烟花爆竹时会释放出大量二氧化硫气体，能污染空气．故B符合题意；

C、燃放烟花爆竹不会产生氢气．故C不符合题意；

D、燃放烟花爆竹不会产生稀有气体．故D不符合题意．

故选B．

填空题

Part 4


Questions 26-45


·Read the following passage and choose the best word for each space.
·For questions 26-45, mark one letter A, B, C or D on the Answer Sheet.
Do you want to send an e-mail message to the White House
Good luck.
In the past, (26) President Bush — or at least those assigned to read his mail — what was (27) your mind it was necessary only to sit down at a personal computer connected to the lnternet and (28) a note to president@ whitehouse.gov.
But this week, Tom Matzzie, an online organizer with the A.F.L.-C.I.O., discovered that (29) with the White House had become a bit more (30) . When Mr. Matzzie sent an e-mail protesting (31) a Bush administration policy, the message was bounced back With an automated reply, saying he had to send it again in a new way.
Under a system (32) on the White House Website (33) the first time last week, those who want to send a message to President Bush must now (34) as many as nine Web pages and (35) a detailed form that starts by asking whether the message sender supports White House policy (36) differs with it.
The white House says the new e-mail system is an effort to be more responsive (37) the public and offer the administration "real time" access (38) citizen comments.
Completing a message to the president also requires (39) a subject from the provided list, then entering a full name, organization, address and e-mail address. (40) the message is sent, the writer must wait for an automated response (41) his message, (42) whether the addressee intended to send the message. The message is delivered to the White House only after the person using that e-mail address (43) it.
"Over (44) , it’s a very cumbersome process," said Jakob Nielsen, an authority on Web design. "It’s probably designed deliberately to (45) on their e-mail.\

A．and

B．or

C．not

D．nor
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判断题

在负载为星形接线的电路中，负载的相电压等于线电压，线电流为相电流的
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