小黄同学做“比较两种材料保温性能”的实验,他取①泡沫塑料和②卫生纸两种作保温材料

题型:问答题

问题:

小黄同学做“比较两种材料保温性能”的实验,他取①泡沫塑料和②卫生纸两种作保温材料,两根相同的温度计,两个相同的大玻璃烧杯,钟表和热开水,以及细线、硬纸片、剪刀.做两个相同的硬纸外壳,其中一个装置如图1所示,根据实验测得的数据绘得图2所示“水温与时间关系”的图象.实验过程室温基本不变,请回答:

(1)你认为小黄在操作时,就控制变量法方面还要注意什么?______.(只要求写出一条)

(2)①和②相比材料______的保温性能较好,理由是______.

(3)当时的室温大约是______.

考点:控制变量法和科学探究的过程
题型:问答题

某学校计划对学生开展口腔保健工作请来了口腔医院的专业人员,与校领导和卫生老师一起研究学校口腔保健计划。

学生的龋齿多发生在牙齿的窝沟点隙,防龋措施应该选择

A.含氟牙膏刷牙

B.学校饮水加氟

C.氟水含漱

D.窝沟封闭

E.窝沟封闭加含氟牙膏

题型:问答题

生姜能减轻或清除生半夏的毒性,这种配伍关系称为()。

A.相须

B.相使

C.相杀

D.相恶

E.相反

题型:问答题
I stood there outside of the classroom  with the other students,waiting for the supervisor(监考老师)to open the door,and   1  filled the heart.
When we were finally inside the classroom,I realized how   2  it was.  The heater hadn't been on and the _3___ were as cold as ice.  Alright then, the supervisor started to walk around,____4___everyone's calculator to make sure they were "approved devices"(允许使用的工具).
At around 8:25,the test started.  I was___5____my way through word problems, grammar sections,and reading and   6  sections.  The supervisor kept walking around the room,    7  each student's extra pencils and   8  sharpening them for us.I turned the___9___when instructed to,___10____it wasn't another math section and it wasn't.  It was a reading section —— ___11____!I started reading the excerpt(片段)given and was    12  to discover that it wasn't a boring piece about astrology (星象)or biological science. ____13____,it was an excerpt from a romantic novel.  I became little____14____with reading it and at times I wanted to say "Awww!”aloud.  My heart was     15       swooning(沉醉)and I think I was   16 .  Hopefully I got the questiotions from that section____17__because I actually had fun answering them.  Who knew the SAT could actually bring   18 
It was about 1 p. m.  when the test was over.  I got out of the classroom  with____19____.As I was walking outside the building,I was thinking that the test was no longer a bitter____20____for the first time in my life.
小题1:
A. happinessB. nervousnessC. calmnessD. sadness
小题2:
A. amazingB. disappointingC. tiringD. freezing
小题3:
A. seatsB. wallsC. floorsD.hearts
小题4:
A. seeingB. takingC. checkingD.preparing
小题5:
A. lookingB. pacingC. makingD. showing
小题6:
A. comprehensionB. thinkingC. guessingD. recitation
小题7:
A. bringing inB. putting downC. picking upD. showing off
小题8:
A. kindlyB. slightlyC. directlyD. slowly
小题9:
A. doorB. directionC. pencilD. page
小题10:A.  finding         B.  praying       C.  deciding     D,  imagining
小题11:
A. terribleB. greatC. sureD. no
小题12:
A. frightenedB. worriedC. shockedD. regretted
小题13:
A. HoweverB. ThereforeC. AlsoD. Rather
小题14:
A. carried awayB. worn outC. tiredD. confused
小题15:
A. suddenlyB. totallyC. overD. again
小题16:
A. readingB. sleepingC. smilingD. whispering
小题17:
A. rightB. readyC. clearD. possible
小题18:
A. hopeB.joyC.interestD. trouble
小题19:
A.reliefB.hungerC.strengthD.courage
小题20:
A.attemptB.factC.processD.experience
题型:问答题

下列选项中,()替代“?”符合所给图形的变化规律。

A.A

B.B

C.C

D.D

题型:问答题

在Java源文件中( )类最多只能有一个,其他类的个数不限。

A.public
B.private
C.protected
D.没有这种类

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