已知A=4x2-4xy+y2，B=x2+xy-5y2，求：
（1）A-3B；
（2）3A+B．
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Ⅱ型客滚船的乘客和船员活动处所的所有梯道均应设置牢固的（）。
あしたは あめらしいです。スポーツたいかいは（ ）かもしれませんね。
A．だめな
B．だめだ
C．だめの
D．だめ
阅读下面的短文，根据短文后的要求答题(请注意问题后的字数要求)。
[1]Do you like chocolate? Most people do．Some like it in bars．Others just like big squares of it．
[2]Say you just got a box of chocolate．Which piece do you pick first? A study carried out by a professor in the University of Virginia showed that people's choices of chocolates show their personality．If you choose a round piece, you are a person who likes to party．If you select an oval shape, you are a person who strives．You like to make things and push yourself to be successful．Picking a square shape shows that this is an honest and truthful person you can depend on．
[3]What kind of chocolate do you pick? Maybe you like milk chocolate．This shows you have warm feelings about the past, while dark chocolate means something else—the person who chooses it looks forward to the future．What about white chocolate? Would you like to choose it? , you may find it hard to make up your mind．Those who like chocolate with nuts are people who like to help others．
[4]Do you believe these ideas? Can chocolate tell all these things? It doesn't matter．There is one sure thing about eaters of chocolates - they eat it because they like it．
小题1:What is the main idea of the text? （no more than 6 words．）
小题2:Fill in the blank (Paragraph 3 Line 3) to complete the sentence（no more than 5 words）
小题3:What does the underlined word “this”(Paragraph 2 Line 4) refer to? （no more than 8 words）
小题4:What’s the writer’s attitude towards the information about chocolate in the text?(no more than 15 words)
小题5:According to the passage, what of chocolate can show your characteristics and qualities?（no more than 2 words）
当直放站某项告警使能关闭时，直放站（）该项告警；此时监控中心查询直放站的该项告警状态，直放站返回该告警项目状态为（）。
A.上报、正常
B.不上报、正常
C.上报、告警
D.不上报、告警
决定碱液在澄清槽内澄清至合格的时间长短主要取决于哪些因素？