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问题 解答题

某飞机着陆生滑行的路程s米与时间t秒的关系式为：s=60t-1.5t2，试问飞机着陆后滑行多远才能停止？

答案

∵-1.5＜0，

∴函数有最大值．

当t=-

60
2×(-1.5)
=20时，

s最大值=

-602
4×(-1.5)
=600，

即飞机着陆后滑行600米才能停止．

阅读理解
阅读理解。
HIGHFIELD COMPREHENSIVE SCHOOL
SCHOOL REPORT
Form Teacher:  G. Baker                  Pupil's Name:  Simon Watkins
Term:         Summer 2010               Form:         B
SubjectExamClass workComments
English5961Simon has reached a satisfactory standard but now needs to apply himself with
 more determination.
Mathematics7785Sound work and progress throughout the year. Well done!
History4653A disappointing exam result. He is unable to give attention to this subject for long.
Chemistry7885His obvious ability in the subject was not fully reflected in his exam work, but I 
have high hopes for him nevertheless.
Physics8694An excellent term's performance. He goes from strength to strength. A born 
scientist, I feel.
Biology5760This time next year he will be taking the 'O' Level exam. He needs to
 concentrate 
on the work, not on class conversation.
French4146Clearly he didn't bother to revise. His general attitude is far too casual.
Physical
Education		31Weak. It's time he exercised his body more and his voice less. He should try 
to work with a team.
FORM TEACHER'S REMARKS                                              HEADMASTER
Basically satisfactory work and progress                   I shall be keeping an eye on his
though he will now have realized, I hope, that             progress in his weaker subjects
in certain subject areas he needs to make speedy       though his success in the sciences is
improvement.                                                most pleasing.
1. According to the comments of the Physical Education teacher, Simon _____.
A. is too talkative in the class
B. likes to work with his classmates
C. doesn't exercise his body at the right time
D. becomes weak because he doesn't exercise at all
2. Which of Simon's subjects will attract the headmaster's attention in future?
A. Biology and Maths.
B. History and French
C. English and Chemistry.
D. Physics and Physical Education.
3. Which of the following statements best describes Simon?
A. He has made great progress in language classes.
B. His potential has been fully reflected in science classes.
C. His grade in maths makes him a born scientist.
D. He needs to improve his attitude on certain subjects.
4. Based on the school report, which of the following statements is true?
A. Simon didn't bother his teacher to revise French.
B. Basically, Simon did a good job in science.
C. Simon is a determined learner in English.
D. Simon is able to pay attention to history for long.
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单项选择题

患者，女，30岁。发现下腹包块1月余，小腹胀痛，痛无定处，舌苔薄润，脉沉弦。其证候是

A．血瘀
B．寒凝
C．气滞
D．痰湿
E．湿郁
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