对长度为n的线性表进行顺序查找,在最坏情况下所需要的比较次数为________。
A.log2n
B.n/2
C.n
D.n+l
参考答案:C
某学校化学兴趣小组的同学做氢氧化钠溶液和稀硫酸中和反应实验时,由于实验中忘记加酚酞试液,不知二者是否恰好完全中和,因此他们对反应后溶液中的溶质是什么提出猜想,并展开探究.
[提出问题]溶液申的溶质可能是什么?
[猜想]他们的猜想:溶质只有硫酸钠;
你的猜想:(1)溶质是______;
(2)溶质是______.
[设计实验]
请选择你的其中一种猜想,设计实验加以证明(答出方法、现象、结论)______.
In the following passage, there are 25 blanks representing words that are missing from the context. You are to put back in each of the blanks with the missing word. Write your answers on the ANSWER SHEET. The time for this section is 25 minutes. Compared with the immediate practical responsibility of the scientist, the (1) of the artist must seem puny. The decision which faces (2) is not one of practical action: of course he will try to throw this (3) into the scale, and that weight, if he is a writer or (4) a painter of genius, may have its effect. For the novelist—in our society the only artist who has a mass audience and at the same time effective economic control of the means of addressing (5) —the hope of some decisive influence is a reasonable (6) . For him, since he takes of all artists (7) is probably the largest portion of his culture as material, there is no (8) escape from the necessity for treating the content of his work seriously than (9) is for the social psychologist he is coming so closely to resemble. The dichotomy which people have tried to establish between artistic proficiency and (10) content is becoming unbearable to almost all sensitive minds. I doubt if it has ever been real— we might have admired Shelley as (11) if he had been indifferent to such things as war and tyranny, though I doubt it; certainly (12) he been indifferent we should never have been led by (13) . There is no Hippocratic oath in literature, and I am not attempting to draw (14) up. As far as I am concerned, the artist is a human being writ large and his (15) are the ethics of any human being. Perhaps I can best illustrate (16) seems to me the new (17) of those duties of assertion and refusal from one writer, and I do not (18) it is without significance that this (19) projects the whole situation of choice into a scientific parable, the (20) of a pestilence: a (21) many human (22) are called to fight against, called not by any supernatural (23) but by the simple fact that the fight against a plague is (24) like a biological human (25) .