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Scientists say they have discovered hints of alien lifeon the Saturn's moon. The discovery of a sort of life was announced after researchers at the US space
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agency,NASA,analyzed data from spacecraft Cassini,which pointed to,the existence of methane-based form of life on Saturn's biggest moon.
Scientists have reportedly discovered clues showing primitive alien beings are\
Titan's dense atmosphere filled with hydrogen.
They argue that hydrogen gets absorbed before hitting Titan's planet-like surface covered
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with methane lakes and rivers. This,they say,points to the existence of some\ consuming the hydrogen at the surface of the moon less than half the size of the Earth.
\Titan,similar to the way we consume oxygen on Earth,\NASA scientist Chris McKay.\these signs do turn out to be a sign of life,it would be doubly exciting because it would represent a second form of life independent from water-based life on Earth.\
To date,scientists have not yet detected this form of life anywhere,though there are liquid-
water-based microorganisms on Earth that grow well on methane or produce it as a waste product.
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On Titan, where temperatures are around 90 Kelvin(minus 290 degrees Farenheit),a methanebased organism would have to use a substance that is liquid as its medium for living processes, but not water itself. Water is frozen solid on Titan's surface and much too cold to support life as we know it.
Scientists had expected the Sun's interactions with chemicals in the atmosphere to produce a coating of acetylene on Titan's surface. But Cassini detected no acetylene on the surface.
The absence of detectable acetylene on the Titan's surface can very well have a
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non-biological explanation,said Mark Allen,a principal investigator of the NASA Titan team.
\conservatism suggests that a biological explanation should be the last choice after all non-biological explanations are addressed,\
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do to rule out possible non-biological explanations. It is more likely that a chemical process,without biology,can explain these results.\1 .What have scientists found about Saturn? A They have found a new moon orbiting Saturn. B They have found methane-based life on Saturn. C They have found methane-based life on Titan.
D They have found earthlike life on a Saturn's moon. 2. What do scientists say about Titan? A There are life clues there. B There is acetylene there.
C Water on Titan exists in the form of ice. D Rivers and lakes there contain life formls. 3. To date,scientists have not yet detected this form of life.(paragraph 5)What does\form of life\A Water-based life.
B Methane-based life.
C Liquid-water-based microorganisms. D Gas-based life.
4. What can be inferred from what Allen said?
A Scientists have different arguments over whether there is life on Titan. B Scientists all agree that there is life on Titan.
C Scientists all suggest that a biological explanation is reasonable.
D Scientists all agree that a non-biological chemical reaction is a possible explanation. 5. Which of the following can replace the title of this passage? A Earthlike Living Beings Found on Titan. B Finding of One More Moon of Saturn. C Titan,a New Satellite Found.
D A different Life Form, a Possibility.
Teaching Math, Teaching Anxiety
In a new study about the way kids learn math in elementary school, the psychologists at the
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University of Chicagol Sian Beilock and Susan Levine found a surprising relationship between what female teachers think and what female students learn:If a female teacher is uncomfortable with her own math skills, then her female students are more likely to believe that boys are better than girls at math.
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\these girls keep getting math-anxious female teachers in later grades, it may create
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a snowball effect on their math achievement said Levine. In other words,girls may end up
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learning math anxiety from their teachers. The study suggests that if these girls grow up believing that boys are better at math than girls are,then these girls may not do as well as they would have if
they were more confident.
Just as students find certain subjects to be difficult, teachers can find certain subjects to be difficult to learn -- and teach. The subject of math can be particularly difficult for everyone. Researchers use the word \to describe such feelings: anxiety is uneasiness or worry.
The new study found that when a teacher has anxiety about math, that feeling can influence how her female students feel about math. The study involved 65 girls,52 boys and 17 first- and
second-grade teachers in elementary schools in the Midwest. The students took math achievement tests at the beginning and end of the school year, and the researchers compared the scores.
The researchers also gave the students tests to tell whether the students believed that a math superstar had to be a boy. Then the researchers turned to the teachers:To find out which teachers were anxious about math,the researchers asked the teachers how they felt at times
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when they came across math, such as when reading a sales receipt. A teacher who got nervous looking at the numbers on a sales receipt, for example,was probably anxious about math.
Boys,on average,were unaffected by a teacher's anxiety. On average,girls with math-anxious teachers scored lower on the end-of-the-year math tests than other girls in the study did.Plus,on the test showing whether someone thought a math superstar had to be a boy,20 girls showed feeling that boys would be better at math -- and all of these girls had been taught by female teachers who had math anxiety.
\in need
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of replication with a larger sample,\
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Missouri in Columbia.
1. What is the result of the research at the University of Chicago,according to the first paragraph?
A Girls comfortable with their own math skills are better than boys at math.
B Girls uncomfortable with their own math skills are not as good as boys at math. C Female teachers' math skills have influence over girl students' math skills.
D Female teachers' confidence in their math skills is related to girl's math skills. 2. What is implied in the third paragraph?
A Math teachers,like math learners,do not like the subject due to its difficulty.
B A difficult subject like math may affect teachers' confidence in teaching the subject. C Teachers are more anxious teaching math than their students learning math. D Math is so difficult that no teachers like to teach it.
3. According to the experiment,those teachers were probably anxious about math when they felt A nervous memorizing the numbers of a sales receipt. B helpless saving the numbers of a sales receipt. C uneasy reading the numbers of a sales receipt. D hopeless filling in the numbers of a sales report.
4. The sixth paragraph tells us that the research findings
A prove a strong link between female teachers' math anxiety and their female students' math achievements.
B show that male students are less likely to be affected by their math anxiety than female students.
C provide strong evidence that math superstars are more likely to be males than females. D discover a strong link between teachers' math anxiety and their students' math achievements. 5. David Geary thinks that
A the study is interesting but it is based on unreliable research process. B the research results need to be retested based on a larger sample. C the research results need to be reinterpreted to be meaningful. D the study is well based and produces significant results.