前方交会法测水平位移的基线长度一般应取（）。A.100～200m B.200～300

设集合A={-1，1，3}，B={a+2，a²+4}，A∩B={3}，则实数a的值为（    ）。

晚上8时是______，15时是下午______．

During the years of depression(萧条), food and money were very hard to find and people had to trade things with each other.  

One day I was   36   some potatoes from Mr Miller. I noticed a small poor boy hungrily   37   a full basket of   38   green peas. Then I was  39   to see that Mr Miller sold the boy a bag of peas   for just a marble (弹球).

Mrs Miller, who had been standing nearby,    40   and told me that Mr Miller loved to  trade with the three boys in the village for peas, tomatoes, and other things  41   he didn’t really need any marbles. I left the stand, smiling to myself,   42   by this man.

Several years went by. One day I learned that Mr Miller had died. I took part in the funeral(葬礼),  43   three young men . They came over to Mrs Miller, hugged her, kissed her on the cheek, spoke with her and moved on,   44   their eyes.

Our 45   came to meet Mrs Miller. I mentioned 46   she had told me about the 47 . She told me,“Those three young men above were the boys I told you about. They just told me   48  they appreciated the things Jim‘traded’with them. Now, at last, they came to pay their debt.”  

“We’ve 49   had a great deal of the wealth in this world,” she added, “but right now, Jim would consider himself to be the  50   man.”

Then she gently lifted the   51   fingers of her husband. Resting underneath were three red marbles.

At that time I realized that we would not be  52    by our words, but by our kind  53  . It is said that it takes a minute to find a    54  person, an hour to appreciate him, a day to love him, but an entire life to  55   him.

James Barry

36.A.buying                 B. selling                      C.borrowing                 D. hunting

37.A.glaring at                 B. glanced at                 C. staring at                  D.watched at

38. A. picking fresh      B.freshly picked            C. picked freshly           D.fresh dried

39. A. astonished           B. amazed                    C. annoyed                   D.worried

40.A.turned over           B.going over                 C. came over                D.coming over

41.A.but                       B. otherwise                 C. or                               D. although

42.A.suspected              B.impressed                 C.regreted                    D.embarrassed

43.A.saw                      B.discovering                C.finding                  D.seeing

44.A.closing                 B.wiped                       C.cleaning                    D.wiping

45.A. time                    B. chance                     C. turn                         D. decision

46.A. the story             B. the proverb          C. the legend                  D. the joke

47.A. marbles               B. men                         C. debt                         D. life

48.A.why                    B. how                         C. when                       D. what

49.A. ever                    B. always                        C. never                       D.seldom

50.A. honest                 B. happiest                   C. coldest                        D. richest

51.A. lifeless                B. regretless                  C. useless                        D. hopeless

52.A. thought               B. touched                    C. remembered             D. affected

53.A.deeds                   B. things                      C. remarks                    D.rewards

54.A. strict                   B. honest                      C. special                            D. learned

55.A.ignore                  B. forget                      C. recognize                 D.remind

患者呼吸困难，血气分析结果：pH7.122，PaCO65.9mmHg，Pa0₂33.0mmHg，HC0₃^-21mmol／L。

目前最需要的治疗是（）.

A.静点碳酸氢钠

B.镇静

C.高浓度吸氧

D.机械通气

E.静点硝酸甘油

在夏天香蕉迅速变甜，这是由于高温利于（）酶的活化，使淀粉水解形成糖的结果。

A.淀粉酶

B.淀粉磷酸化酶

C.R酶

D.R酶和麦芽糖酶