某校要从甲、乙两名跳高运动员中挑选一人参加一项比赛,在最近的8次选拔赛中,他们的

题型:解答题

问题:

某校要从甲、乙两名跳高运动员中挑选一人参加一项比赛,在最近的8次选拔赛中,他们的成绩(单位:m)如下:

甲:1.70,1.67,1.68,1.67,1.72,1.73,1.68,1.67

乙:1.60,1.73,1.75,1.61,1.62,1.71,1.75,1.75

(1)他们的平均成绩分别是多少?

(2)哪个人的成绩更为稳定?请说明理由.

(3)经预测,跳高1.65m就很可能获得冠军,该校为了获取跳高比赛冠军,可能选哪位运动员参赛?若预测跳高1.70m方可获得冠军呢?请说明理由.

考点:平均数方差
题型:解答题
下列有关电阻的说法不正确的是(  )

A.由R=U/I可知,电阻与电压、电流均有关

B.由R=ρl/S可知,电阻与导体的长度和横截面积都有关系

C.热敏电阻的温度越高,其ρ越小

D.用超导体做成的导体,电阻为零,故不发热

题型:解答题

如图所示,某同学在做俯卧撑,如果将他视为一个杠杆,他的重心在A点,重力为500N,若每次肩部上升的距离均为0.4m,那么他每次将身体撑起所做的功至少为 ___________ J。

题型:解答题

脑瘤诊断的首选检查为()

A.脑室造影

B.颅骨X线平片

C.CT扫描

D.脑血管造影

E.脑超声波

题型:解答题

阅读理解

     On the first day of my new high school,I almost had a nervous breakdown. Everything about the

school seemed so difficult. When I got home, my parents said, "You're nervous and that's okay.

Everyone is afraid of high school." I denied it. I wanted to be strong, so I refused to let anyone know

about my fear,even my closest friends.

     On the first day I was late for every class and was constantly lost. The school seemed like a puzzle

that I couldn't figure out. Was this how the whole year was going to be? I didn't think I could rise to this

challenge, especially carrying a huge backpack that I could hardly lift. It was so big that I could knock

someone out with it! The schoolmates seemed to regard me as a fool, and they were probably right.

     Despite my fears, after the first week I finally had my schedule figured out. With the exception of

falling up and down the stairs a couple of times and getting laughed at,high school was turning out to be

not so bad. It was actually much better than middle school and much more challenging.

Since then,I've been elected vice monitor of my class,which wasn't much of a victory since only three

people ran for the four positions.

     It is normal to be scared about a new school. Take a deep breath and relax. High school is

something that any student can overcome. Make sure you participate in some outofclass activities

because you'll find it easier to make friends. Try to do your best, even if it isn't straight A's.

     Most important of all, be who you are, whether you're a "fool", an athlete, or a lower grader. Don't

try to pretend to be someone you're not. Now you know the true secrets of high school.

1. The main reason for the author's fear on his first day is that ________.

A. he was unable to work out the puzzle

B. his schoolmates were unfriendly to him

C. he was not familiar with the new surroundings

D. his schoolbag was too heavy for him to carry

2. From the author's first day experience we can infer that ____.

A. his home was far from the school

B. he got to school after classes began

C. he didn't get any school schedule

D. he didn't know the right way to class

3. After his first week at school,the author ________.

A. was still not accustomed to the schedule

B. gradually adjusted himself to the new school

C. found high school not so challenging as he had imagined

D. ran for monitor of his class against three other students

4. According to the passage,the secret of the author's success lies mainly in ________.

A. making more friends

B. getting more A's at school

C. being who he really is

D. joining in outofclass activities

题型:解答题

在满足其他授权条件的情况下,下列哪些申请能被授予发明专利权()

A.申请专利的发明是依赖遗传资源完成的,但该遗传资源的利用违反了行政法规

B.同一申请人同日对同样的发明创造既申请实用新型专利又申请发明专利,申请人不放弃其先获得的实用新型专利权的

C.未经保密审查,将在中国完成的发明在外国申请专利后,再到中国申请专利的

D.职务发明的发明人私自将其做出的发明以自己名义申请专利的

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