学进去-教育应平等而普惠
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已知函数
(1)当时,讨论函数的零点个数;
(2)当时,证明:
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如图所示,在竖直平面内有一足够长的绝缘轨道水平放置,竖直放置,轨道粗糙,是绝缘光滑的四分之一圆弧形轨道,圆弧的圆心为O,半径,轨道所在空间存在水平向右的匀强电场,电场强度的大小。现有质量,电荷量的带电体(可视为质点),从A点由静止开始运动,已知距离1m,带电体与轨道间的动摩擦因数均为0.5,假定带电体与轨道之间的最大静摩擦力和滑动摩擦力相等。(取g=10m/s2)求:
(1)求带电体首次运动到圆弧轨道C点时对轨道的压力;
(2)带电体最终停在何处;
(3)如果电场强度的大小可在0到范围内调节,当E取不同值时,求带电体全程摩擦产生的热量。
类型:解答题
难度系数:困难0.15
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,函数的图象与直线相切,其中是自然对数的底数.
(1)求实数的值;
(2)当时,恒成立,求实数的取值范围.
类型:解答题
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在平面直角坐标系中,已知点,点满足.记的轨迹为
(1)求的方程;
(2)已知直线,若点关于直线的对称点(与不重合)在上,求实数的值;
(3)设直线的斜率为,且与有两个不同的交点,设,直线的另一个交点为,直线的另一个交点为,若点和点三点共线,求实数的值.
类型:解答题
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对于一个列的数表,用表示数表中第行第列的数,其中,且数表满足以下两个条件:

,规定
(1)已知数表中,.写出的值;
(2)若,其中表示数集中最大的数.规定.证明:
(3)证明:存在,对于任意,有
类型:解答题
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假如你是学生会主席,你发现新高三学生在学习的重压下养成了很多不健康的生活方式。请代表学生会,就此现象为校报“英语广场”栏目写一份倡议书。内容包括:
1. 你的发现;
2. 你的倡议。
注意:
1. 词数80左右;
2. 可以适当增加细节,以使行文连贯。
Dear fellow students,
______________________________________________________________________________________________________________________________________________________________________________________

The Student Union

August 8, 2022

类型:其他应用文
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What to Do With a Day Off

If you're fortunate enough to have today off from work, the most important thing on your to-do list is to actually take the day off. Studies have shown that people send only 40 percent less email on holiday Mondays compared with regular Mondays. 1. Here are a few suggestions on how best to spend your day off.

Evaluate your career.

When was the last time you were completely honest with yourself about your career and whether you're doing what you want to be doing? 2. A full-time worker will spend roughly 80.000 hours at work during her working life, so if you're in the wrong career that could mean tens of thousands of hours spent devoted to something you don't even really care about, much less to feel   your passion.

Have a family meal.

3. Work, school,sports practices and other obligations all seem to get in the way. But studies show that families who dine at home together are happier and healthier.

4.

“I'll get to it sometime." Yeah, yeah, it's what we all tell ourselves to get out of doing the things on our to-do list that are hanging over our heads. But today is a great day just to get it done! Send that email, finish up that task at home, send that holiday thank-you note you still haven't gotten around to. Whatever it is,just do it. 5.

A.You'll feel so much better,I promise.
B.It might even make you more productive at work this week.
C.It can be tough to get the whole family together for a meal.
D.Besides, taking time to let your brain rest and recover makes you better at problem-solving.
E.Spend more quality time with your family by having a family meal.
F.If you're like most people, probably not recently.
G.Do that one thing you've been putting off.
类型:七选五
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Background noise—like the chatter in a coffee shop or the drone of passing traffic—might slow our reading speed, but according to a study of Russian readers, it doesn’t _________ how our brain understands written text.

_________, if you’re wondering whether you should be listening to podcasts or music while working, the study has some interesting points to make. In particular, it examined how we might change our reading style to compensate for auditory noise and visual distractions such as typos or poor formatting.

“Overall, previous studies reported a harmful effect of both auditory and visual noise on reading fluency and _________, though their results varied,” write linguistics researcher Nina Zdorova and colleagues. “So far, none of the studies exploring the influence of noise _________ it in the framework of the language processing theories.”

One of the language processing theories examined was the noisy channel model, which proposes that our brain deals with noise by looking at the meaning of _________ words more and at entire sentences less. We then use a bit of smart guesswork to _________ the overall meaning and relationships between words.

The second theory is the good enough model; that’s when our brains aren’t analyzing every single detail of a text but instead only grabbing enough words for a ‘good enough’ understanding. By focusing less on the precise words, our brains can _________ some cognitive resources to deal with noise.

To see how reading was affected by noise _________ these models, the researchers ran two experiments: one on auditory noise (71 participants) and one on visual noise (70 participants). When it came to the auditory noise test, background chatter from overlapping podcasts caused people to spend longer looking at the key section of sentences before completing their reading. This extra time could _________ the noise, meaning sentence comprehension isn’t affected by it. In the visual noise test, comprehension remained the same while reading speed __________. That’s a bit __________ considering previous studies, but the researchers think people just wanted to finish the task, with the visual noise an uncomfortable distraction.


“In both experiments, we observed that longer total reading time was __________ with an accuracy increase for incorrect sentences,” write the researchers.

There’s a lot going on in this study, but overall it’s a bigger win for the good-enough language processing theory and an indication that auditory and visual noise doesn’t make us __________ any more or less on any particular comprehension method while we’re reading.

With so many variables to measure in terms of what’s being read and what the __________ noise is, further study is required to learn more. __________ potential distractions may not interrupt your reading as much as you think.

1.
A.reinforceB.estimateC.affectD.interpret
2.
A.First of allB.For exampleC.Above allD.To start with
3.
A.contextB.efficiencyC.comprehensionD.device
4.
A.evaluatedB.identifiedC.establishedD.employed
5.
A.individualB.differentC.newD.unfamiliar
6.
A.confirmB.implyC.referD.infer
7.
A.exploitB.spareC.commitD.consume
8.
A.on account ofB.regardless ofC.in regard toD.in contrast to
9.
A.make up forB.live up toC.catch up withD.put up with
10.
A.declinedB.shrankC.expandedD.increased
11.
A.embarrassingB.depressingC.puzzlingD.annoying
12.
A.associatedB.comparedC.replacedD.mixed
13.
A.takeB.setC.relyD.base
14.
A.accompanyingB.strangeC.deafeningD.distant
15.
A.ThereforeB.HoweverC.InsteadD.Otherwise
类型:完形填空
难度系数:困难0.15
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Scientists have discovered more than 5,000 new species living on the seabed in an untouched area of the Pacific Ocean that has been identified as a future hotspot for deep-sea mining, according to a review of the environmental surveys carried out in the area.

It is the first time the previously unknown biodiversity of the Clarion-Clipperton Zone (CCZ), a mineral-rich area of the ocean floor that spans 1.7m sq miles between Hawaii and Mexico in the Pacific, has been comprehensively documented. The research will be critical to assessing the risk of extinction of the species, given contracts for deep-sea mining in the near-pristine area appear imminent.

Most of the animals identified by researchers exploring the zone are new to science, and almost all are unique to the region: only six, including a carnivorous sponge and a sea cucumber, have been seen elsewhere.

Contracts for mining exploration in the CCZ have been granted to 17 deep-sea mining contractors in an area covering 745,000 sq miles. The companies, which are backed by countries including Britain, the US and China, want to dig for minerals including cobalt manganese and nickel in part to sell to the alternative energy sector.

To better understand the impact of mining this fragile ecosystem and its newly discovered inhabitants, an international team of scientists has built the first “CCZ checklist” by compiling all the records from expeditions to the region. Published in the journal Current Biology, it includes 5,578 different species, of which an estimated 88% to 92% had never before been seen.

To study and collect specimens (样品) from the ocean floor, biologists have joined research cruises in the Pacific that send remote-controlled vehicles to traverse (穿越) the seabed 4,000 to 6,000 meters below. Adrian Glover, a deep-sea biologist at the NHM and senior author of the study described it as an “incredible privilege”. The expedition, funded through the Natural Environment Research Council and others, is backed by UK Seabed Resources (UKSR), a deep-sea mining company that operates the UK’s exploration area. The scientists watch operations by video link direct from the boat as new species are gathered by remote control vehicles in the darkness below.

The seabed, Glover said, is an “amazing place” where, despite the extreme cold and dark, life thrives. “One of the characteristics of the abyssal plain is the lack of food, but life has a way of persisting down there,” he said, “It’s a mystery.” One of the deep-sea animals discovered was nicknamed the “gummy squirrel”, because of its huge tail and jelly-like appearance, he said. There are also glass sponges, some of which look like vases.

With approval for deep-sea mining looming, Glover said he believed it was “imperative that we work with the companies looking to mine these resources to ensure any such activity is done in a way that limits its impact upon the natural world”.

1.What’s the meaning of the underlined word “imminent”?
A.Easy to carry out.B.Ready to take place.
C.Hard to cope with.D.Important to look over.
2.What is the primary focus of the research in Clarion-Clipperton Zone (CCZ)?
A.Identifying new species living on the seabed.B.Assessing the risk of extinction of species.
C.Documenting the biodiversity of the area.D.Exploring the potential for deep-sea mining.
3.What is the feature of the abyssal plain mentioned by Adrian Glover?
A.Abundance of food.B.Extreme lifeless environment.
C.Presence of glass sponges.D.Prosperous life despite challenging conditions.
4.What’s the best title of the passage?
A.A magic zone:available to mining companies
B.A mineral-rich area: Clarion-Clipperton Zone
C.An “amazing place”: new species booming
D.Deep-sea wonders: the new species found in a Pacific mining hotspot
类型:阅读选择
难度系数:困难0.15
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已知,则(       
A.B.
C.D.
类型:单选题
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