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小明的妈妈是一个手机控,她一有时间总是抱着手机不停地刷屏.有一次她连续刷屏2个小时,使手机温度明显升高.手机温度升高是因为电流的效应;如果手机工作时的总电阻是12欧姆,工作电流为250mA,那么,她刷屏2个小时,手机一共能产生J的热量.用充电器给手机电池充电时,电池和充电器都会明显发热,但连接手机和充电器的导线却无明显发热,是因为它们的不同.
如图,点A在第二象限内,AC⊥OB于点C,B(-6,0),OA=4,∠AOB=60°,则△AOC的面积是.

如图,已知直线y=2x+4与x轴交于点A,与y轴交于点B,以点A为圆心,AB为半径画弧,交x轴正半轴于点C,则点C的坐标为(   )

A . B . C . D .
下面关于能量转化的说法,正确的是(   )
A . 用砂轮磨刀时,将内能转化为动能 B . 陨石进入大气层成为流星时,是内能转化为机械能 C . 壶中的水沸腾,壶盖不断跳动,是水的势能转化为壶盖的动能 D . 用打气筒给轮胎打气时,打气筒发热,是机械能转化为内能
去产能是我国供给侧结构性改革的五大任务之一。2016年,随着煤炭行业去产能的不断推进,进口焦煤价格从85美元左右持续上涨到260美元,国内焦煤价格也涨了1.5倍以上,许多钢铁企业因此效益下滑,甚至亏损,一些停产的小煤矿,则趁机复产。对此现象的正确认识是( )

①遵循市场规律因地制宜去产能,因为联系是客观的

②要防控去产能带来的不良后果,因为联系是人为的

③去产能和稳煤价不能同时兼得,因为联系是具体的

④要把握去产能政策的双重影响,因为联系是多样的

A . ①② B . ①④ C . ②③ D . ③④
某医院病理室为确诊一患者的肝组织肿瘤是良性还是恶性,切取了一小块肿瘤组织进行培养.请回答下列问题:

(1)化疗是抑制肿瘤组织增殖的一种方法,其原理是用药物抑制肿瘤细胞的 ,使细胞分裂停止在分裂间期.

(2)某科研单位研制出一种新型药物P,能有效抑制肝癌细胞的增殖,但不知道对造血干细胞的增殖是否有副作用.为验证其疗效并探究其副作用,请你利用以下材料和用具,完成实验步骤,并用柱状图的形式呈现实验结果.

材料和用具:已知起始数量的肝癌细胞和造血干细胞、动物细胞培养液、用生理盐水配置的药物P、生理盐水、培养瓶、CO2培养箱等.(要求与说明:提供的细胞均具有分裂能力,只进行原代培养且条件适宜,肝癌细胞与造血干细胞的具体计数方法不作要求.)

Ⅰ.实验步骤:

 .

 .

③将上述细胞培养瓶放在CO2培养箱中,在相同且适宜的条件下培养一段时间.

④一段时间后取出观察、并记录各组细胞的数目.

Ⅱ.若结果显示药物P只对肝癌细胞有效,请在坐标系中以柱状图的形式呈现该结果 .

如图,点C是以AB为直径的半圆上任意一点, , 连接AC,将线段AC绕点A逆时针旋转120°得到线段 , 则的最大值为.

有关网络常见术语的描述正确的是(    )
A . SMTP协议用于发送邮件到收件人的电脑 B . HTTPS是一种加密的超文本传输协议 C . 网页内容经常用URL来描述 D . 浏览网页经常使用ftp协议
870-(327+273)×5.5÷4,最后一步计算(    )。
A . 加法 B . 减法 C . 乘法 D . 除法
A、B两个物体从同一地点沿同一直线做匀变速直线运动,它们的v—t图象如图所示,则(   )

图片_x0020_100004

A . A,B两物体加速度相同 B . t=4s时,A,B两物体相遇 C . t =2s时,A,B两物体运动方向相反 D . 在相遇前,A,B两物体最远距离20m
阅读下列短文,从每题所给的A、B、C和D四个选项中,选出最佳选项。

Have you ever heard of agritourism(农业旅游)  through which you can experience farm life? If not, Dr. Cindy Ayers Elliott will tell you the real story of Foot Print Farms.

The original concept of building Foot Print Farms was simple. When Cindy Ayers Elliott returned to her hometown after graduation, she didn't have to look any further than her state's alarming health statistics to find a mission. Everywhere she went, there were reports of high blood pressure, diabetes, obesity and heart disease. "The problem was already identified," explains she. "Too many Mississippians were seriously unhealthy and it didn't take research to see that. And many of the state's greatest health challenges could directly result from poor diet. "

These days, Foot Print Farms, which started with a few raised beds of herbs and vegetables, is making fresh, naturally grown food. "When speaking of the key to my success, the co-op model works because we share the work and rewards," notes Cindy Ayers Elliott. "A perfect example is the Wingfield High School football team. To earn the money for equipment and other items, players were committed to working five hours a week on the farm, and by the end of the summer they had produced 1,000 melons and the profits from their sales helped to buy weights, T-shirts, sweatsuits and pregame meals. But the lessons they learned about the rewards of hard work and working together to accomplish something were even more valuable products of their efforts. "

"It's a model that can easily be learned in other places and I'm looking forward to seeing some of our current partners do just that," she remarks. She is now looking forward to developing an agritourism aspect of the farm, where visitors can experience farm life, learn new skills and take seeds of inspiration they can sow in their own communities with them when they return home.

  1. (1) What made Cindy Ayers Elliott set up Foot Print Farms?
    A . The problems faced by local farmers. B . Her further research into heart disease. C . The failure of her career after graduation. D . The health state of people in her hometown.
  2. (2) Why does the author take the football team as an example?
    A . To explore the key to success. B . To support the idea of the co-op model. C . To stress the importance of teamwork. D . To advocate the concept of independence.
  3. (3) What is Cindy Ayers Elliott's attitude towards the future of Foot Print Farms?
    A . Optimistic. B . Skeptical. C . Cautious. D . Pessimistic.
  4. (4) What is the main idea of the text?
    A . Naturally grown food benefits people's health. B . Agritourism is becoming increasingly popular in America. C . Cindy Ayers Elliott encourages people to experience farm life. D . Food Print Farms is making a difference in Mississippi.

如右图,分别用大小相等的力拉或压同一弹簧。该实验表明,弹簧受力产生的效果与力的         (   )

A . 大小、方向、作用点都有关 B . 作用点有关 C . 大小有关 D . 方向有关
读某校平面图,运动场在教学楼的(    )

A . 西北方向 B . 东北方向 C . 西南方向 D . 正南方向
求下列函数定义域
  1. (1)
  2. (2)
下面是某报刊亭一个月卖出的杂志情况统计表。

种类

时尚

经济

旅游

饮食

娱乐

数量(本)

360

250

200

225

150

  1. (1) 把上面的统计表制成条形统计图。

  2. (2) 时尚类杂志的单价在11元-30元之间,这个月时尚类杂志的销售额大约是(   )元。
    A . 3000 B . 3500 C . 6000 D . 10900
  3. (3) 根据这个月销售情况,对下月进货有什么建议?
“秦以前,民皆以金玉为印,龙虎钮,唯其所好。秦以来,天子独以印称玺,又独以玉,群臣莫敢用”(《史记集解》)。这一材料反映的实质问题是( )

A . 秦朝时期人们以金玉为印 B . 皇权至上,皇帝独尊 C . 秦以前玉玺为皇帝独有 D . 皇权为民,与民共享
下列关于电学知识说法正确的是(   )
A . 自由电荷移动就会形成电流 B . 人站在地面上直接用手拿着铜棒与丝绸摩擦,摩擦后铜棒不带电 C . 根据R= 的电阻与电压成正比,与电流成反比 D . 铜导线中自由电子定向移动的方向就是电流方向
为划线字选择正确的读音。

率(pín  bīn)    纷(bīn  bīng)    应(dā  dá)

藏(zhù  chù)    乎(jī  jǐ)   息(shāo  shào)

现有混入少量二氧化碳的一氧化碳气体,某同学欲用纯净、干燥的一氧化碳还原氧化铁,并验证反应的一种产物。根据如图所示实验装置回答(其中A处框图表示盛有CO2和CO混合气体的贮气瓶):

  1. (1) 请用管口小写字母标号表示装置连接的正确顺序(每种装置只能用一次)A→
  2. (2) B装置的作用是
  3. (3) 请设计实验证明,实验后装置D中溶液的溶质成分。(写出实验步骤、现象和结论)
“每人前进一小步,社会前进一大步。”这表明( )

①个人离不开社会,人们总是生活在一定的社会关系之中          ②人们的生存和发展总是离不开社会所提供的种种条件

③人们的生产劳动、科学研究等活动推动着社会的进步和发展   ④任何社会的存在和发展,都是人们共同努力的结果

A . ①② B . ③④ C . ①②③ D . ①②③④
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