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设三阶方阵A=(α，γ1，γ2)，B=(β，γ1，γ2)，其中α，β，γ1，γ2均为三维列向量，且｜A｜=2，｜B｜=4，则｜2A-3B｜=______．
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John had not much affection for his mother and sisters, and an antipathy to me. He bullied and punished me; not two or three times in the week, nor once or twice in the day, but continually: every nerve I had feared him, and every morsel of flesh in my bones shrank when he came near. There were moments when I was bewildered by the terror he inspired, because I had no appeal whatever against either his menaces or his inflictions; the servants did not like to offend their young master by taking my part against him, and Mrs. Reed was blind and deaf on the subject: she never saw him strike or heard him abuse me, though he did both now and then in her very presence, more frequently, however, behind her back. Habitually obedient to John, I came up to his chair: he spent some three minutes in thrusting out his tongue at me as far as he could without damaging the roots: I knew be would soon strike, and while dreading the blow, I mused on the disgusting and ugly appearance of him who would presently deal it. I wonder if he read that notion in my face; for, all at once, without speaking, he struck suddenly and strongly. I tottered, and on regaining my equilibrium retired back a step or two from his chair. "That is for your impudence in answering mama awhile since," said he, "and for your sneaking way of getting behind curtains, and for the look you had in your eyes two minutes since, you rat!" Accustomed to John Reed’s abuse, I never had un idea of replying to it; my care was how to endure the blow which would certainly follow the insult. "What were you doing behind the curtain" he asked. "I was reading." "Show the book." I returned to the window and fetched it thence. "You have no business to take our books; you are a dependent, mama says; you have no money; your father left you none; you ought to beg, and not to live here with gentlemen’s children like us, and eat the same meals we do, and wear clothes at our mama’s expense. Now, I’ll teach you to rummage my bookshelves: for they are mine; all the house belongs to me, or will do in a few years. Go and stand by the door, out of the way of the mirror and the windows." I did so, not at first aware what was his intention; but when I saw him lift and poise the book and stand in act to hurl it, I instinctively started aside with a cry of alarm: not soon enough, however; the volume was flung, it hit me, and I fell, striking my head against the door and cutting it. The cut bled, the pain was sharp: my terror had passed its climax; other feelings succeeded. "Wicked and cruel boy!" I said. "You are like a murderer--yon are like a slave-driver--yon are like the Roman emperors" I had read Goldsmith’s History of Rome, and had formed my opinion of Nero, Caligula, etc. Also I had drawn parallels in silence, which I never thought thus to have declared aloud. "What] what]" he cried. "Did she say that to me Did you hear her, Eliza and Georgiana Won’t I tell mama but first--" He ran headlong at me: I felt him grasp my hair and my shoulder: he had closed with a desperate thing. I really saw hi him a tyrant, a murderer. I felt a drop or two of blood from my head trickle down my neck, and was sensible of somewhat pungent suffering: these sensations for the time predominated over fear, and I received him in frantic sort. I don’t very well know what I did with my hands, but he called me "Rat! Rat!" and bellowed out aloud. Aid was near him: Eliza and Georgiana had run for Mrs. Reed, who was gone upstairs: she now came upon the scene, followed by Bessie and her maid Abbot. We were parted: I heard the words-- "Dear! Dear! What a fury to fly at Master John!" "Did ever anybody see such a picture of passion!" Then Mrs. Reed subjoined-- "Take her away to the red-room, and lock her in there." Four hands were immediately laid upon me, and I was borne upstairs. What did "I" finally do to John
某建筑公司承接一大厦，总建筑面积1.9万m2，地上20层，地下1层，采用现浇剪力墙结构，混凝土采用商品混凝土，强度等级有C25、C30、C35级，钢筋采用 HPB235和HRB335级。屋面防水采用SBS改性沥青防水卷材，外墙面喷涂。 依据规范规定，混凝土的抗压强度等级分为14个等级。下列关于混凝土强度等级级差和最高等级的表述中，正确的是( )。
Aesthetic thought of a distinctively modem bent emerged during the 18th century. The western philosophers of this time devoted much attention to such matters (31) natural beauty and representation. (32) that time, however, the philosophy of art has become ever more (33) and has begun to (34) the philosophy of nature. Various issues (35) to the philosophy of art have had a (36) impact (37) the orientation of 20th century aesthetics. (38) among these are problems relating to the theory of art as form and (39) the distinction between representation end expression. Still another question has to do with the value of art. Two opposing theoretical positions (40) on this issue: one holds that art and its appreciation are a means to some recognized moral good, (41) the other maintains that art is intrinsically valuable end is an end in itself. Underlying this whole issue is the concept of taste. In recent years there has also been an increasing (42) with art as the prime object of critical judgment. Corresponding to the trend in contemporary aesthetic thought, (43) have followed (44) of two approaches. In one, criticism is restricted to the analysis end interpretation of the work of art. (45) , it is devoted to articulating the response to the aesthetic object and to (46) a particular way of perceiving it. Over the years, aesthetics has developed into a broad field of knowledge end inquiry. The concerns of contemporary aesthetics include such (47) problems as the nature of style and its aesthetic significance; the relation of aesthetic judgment to culture; the (48) of a history of art; the (49) of Freudian psychology and other forms of psychological study to criticism; and the place of aesthetic judgment in practical (50) in the conduct of everyday affairs.
Predictions of many robots in industry have yet come true. For ten years or more, manufacturers of big robots have explained how their machines can make industry more competitive and productive. The maker for (21) robots is oversupplied now, and the driving force of the robotics(机器人学) revolution is (22) to be with makers of machines that handle a few kilos at most."Heavy-robot manufacturers are in some difficulty (23) finding customer. They are offering big (24) just to get in the door. There has been a (23) growth everywhere in the numbers of robots, so we admit we are either deceiving (26) or that the market is slowly growing. "said John Reekie, chairman of Colen Robotics. "The following things must happen (27) the robotics revolution to occur. We must achieve widespread robot literacy, (28) there has been a computer (29) program, there must be a robot prices. (30) , some kind of artificial intelligence needs to be (31) ."Colen makes educational robots and machine tools. It is small (32) with companies like ASEA or Fujitsu Fanuc. But Colen with others and departments in universities such as Surrey, Manchester, and Durham possess an advantage (33) . the giants. The big companies sell very expensive (34) to businesses with expert knowledge in automation. The (35) companies make robots for teaching people, and now they have realized that there is a need for small, (36) robots that they can meet.The little companies either bring their educational machines (37) an industrial standard or design from the start. One technique that they all adopt is to choose (38) components where possible. The major cost of making (39) their models is the electronics, which will fall in price. There is (40) scope for reductions in mechanical costs. The sue of standard parts, which are easily replaced, should give these robots a mechanical life of something in the order of five years. 36().
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