[問題] Prep T1 Q17

[Ivy-Canada]

17. (27669-!-item-!-188;#058&003302)

Urban air contains more sulfur dioxide than does rural air, and plants in cities typically grow more slowly than do plants in rural areas. In an experiment to see how much of the difference in growth is due to sulfur dioxide, classes in an urban and a rural school grew plants in greenhouses at their schools and filtered the greenhouse air to eliminate sulfur dioxide. Plants in the urban greenhouse grew more slowly than those in the rural greenhouse.

Which of the following, if true, would it be most important to take into account in evaluating the result?

(A) The urban school was located in a part of the city in which levels of sulfur dioxide in the air were usually far lower than is typical for urban areas.
(B) At both schools, the plants in the greenhouses grew much more quickly than did plants planted outdoors in plots near the greenhouses.
(C) The urban class conducting the experiment was larger than the rural class conducting the experiment.
(D) Heavy vehicular traffic such as is found in cities constantly deposits grime on greenhouse windows, reducing the amount of light that reaches the plants inside.
(E) Because of the higher levels of sulfur dioxide in the air at the urban school, the air filters for the urban school's greenhouse were changed more frequently than were those at the rural school.

我是選E. 不過答案是D. E不好是因為不管air filters有沒有被changed more frequently那個green house 還是保持著sulfur dioxide free 嗎? 不然我總覺得E也是可以. 謝謝大家的幫忙!!

[Austing]

17. (27669-!-item-!-188;#058&003302)

Urban air contains more sulfur dioxide than does rural air, and plants in cities typically grow more slowly than do plants in rural areas. In an experiment to see how much of the difference in growth is due to sulfur dioxide, classes in an urban and a rural school grew plants in greenhouses at their schools and filtered the greenhouse air to eliminate sulfur dioxide. Plants in the urban greenhouse grew more slowly than those in the rural greenhouse.

Which of the following, if true, would it be most important to take into account in evaluating the result?

(A) The urban school was located in a part of the city in which levels of sulfur dioxide in the air were usually far lower than is typical for urban areas.
(B) At both schools, the plants in the greenhouses grew much more quickly than did plants planted outdoors in plots near the greenhouses.
(C) The urban class conducting the experiment was larger than the rural class conducting the experiment.
(D) Heavy vehicular traffic such as is found in cities constantly deposits grime on greenhouse windows, reducing the amount of light that reaches the plants inside.
(E) Because of the higher levels of sulfur dioxide in the air at the urban school, the air filters for the urban school's greenhouse were changed more frequently than were those at the rural school.

我是選E. 不過答案是D. E不好是因為不管air filters有沒有被changed more frequently那個green house 還是保持著sulfur dioxide free 嗎? 不然我總覺得E也是可以. 謝謝大家的幫忙!!

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原文reasoning: sulfur dioxide的多寡影響到植物的生長速度

(D) Heavy vehicular traffic such as is found in cities constantly deposits grime on greenhouse windows, reducing the amount of light that reaches the plants inside.
因為窗上的灰塵 植物吸收不到光線 所以生長速度慢 直接weaken結論 說明了不是因為sulfur dioxide的多寡 而是因為光線影響到了生長速度

(E) Because of the higher levels of sulfur dioxide in the air at the urban school, the air filters for the urban school's greenhouse were changed more frequently than were those at the rural school.
air filter跟原文的結論無關(out of scope)

[Ivy-Canada]

oh~我瞭解了. 我一直以為filter掉sulfur dioxide 是主要的點. urban 有filter比較多次, rural 比較少次. 不過其實照E) 來看的話urban filter比較多次所以filter的比較徹底的話應該植物會長的比較快, 而不是像文章中說的長的比較慢. 可以從這個觀點來解題嗎?

[小花]

為何原文要提到filtered the greenhouse air to eliminate sulfur dioxide?

[amazingslim]

Urban air contains more sulfur dioxide than does rural air, and plants in cities typically grow more slowly than do plants in rural areas. In an experiment to see how much of the difference in growth is due to sulfur dioxide, classes in an urban and a rural school grew plants in greenhouses at their schools and filtered the greenhouse air to eliminate sulfur dioxide. Plants in the urban greenhouse grew more slowly than those in the rural greenhouse

作者發現
1.都市空氣有比較多的二氧化硫
2.在都市植物生長慢
為了要確定兩者是不是有關，所以排除二氧化硫來做實驗