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105年
[資訊科學組] 綜合法政知識與英文(包括中華民國憲法、法學緒論、兩岸關係、英文)
第 45 題
📖 題組：
請依下文回答第 44 題至第 47 題 Some 66m years ago Earth was hit by a space rock reckoned to have been 10km across. The resulting chaos caused the extinction of dinosaurs and many other species, opening the way for the age of mammals－and ultimately humans. It also left a big hole in what is now southern Mexico. That hole is one of only three known of similar dimensions (the other two are Vredefort in South Africa and Sudbury in Canada). And this is odd. For, during the billions of years that Earth has had a solid crust, many more than three big asteroids might have been expected to have hit it. That thought led Brandon Johnson of the MIT and Timothy Bowling of Purdue University in Indiana, to wonder how many other craters have vanished, either by erosion or by being swallowed into Earth’s interior as its crust moves around, and therefore whether it is likely that some have survived and been overlooked. They have just published their analysis in Geology. Earth’s crust formed more than 4 billion years ago, but the oldest surviving blocks of it large enough to harbor craters date back only 3.5 billion years. What is known of the sizes and orbits of modern asteroids suggests that, if things have not changed over the aeons, about 14 big asteroids (defined as having a diameter of more than 7.4km, which would cause a crater at least 85km in diameter) should hit Earth every billion years. That means 49, give or take seven, over the past 3.5 billion years. Such impacts may have been more common in the past, when more big asteroids were around. Allowing for this, Earth would have been hit by 113, give or take 11, of them. Either way, a lot of craters are missing.
請依下文回答第 44 題至第 47 題 Some 66m years ago Earth was hit by a space rock reckoned to have been 10km across. The resulting chaos caused the extinction of dinosaurs and many other species, opening the way for the age of mammals－and ultimately humans. It also left a big hole in what is now southern Mexico. That hole is one of only three known of similar dimensions (the other two are Vredefort in South Africa and Sudbury in Canada). And this is odd. For, during the billions of years that Earth has had a solid crust, many more than three big asteroids might have been expected to have hit it. That thought led Brandon Johnson of the MIT and Timothy Bowling of Purdue University in Indiana, to wonder how many other craters have vanished, either by erosion or by being swallowed into Earth’s interior as its crust moves around, and therefore whether it is likely that some have survived and been overlooked. They have just published their analysis in Geology. Earth’s crust formed more than 4 billion years ago, but the oldest surviving blocks of it large enough to harbor craters date back only 3.5 billion years. What is known of the sizes and orbits of modern asteroids suggests that, if things have not changed over the aeons, about 14 big asteroids (defined as having a diameter of more than 7.4km, which would cause a crater at least 85km in diameter) should hit Earth every billion years. That means 49, give or take seven, over the past 3.5 billion years. Such impacts may have been more common in the past, when more big asteroids were around. Allowing for this, Earth would have been hit by 113, give or take 11, of them. Either way, a lot of craters are missing.
Over the past 3.5 billion years, roughly how many asteroids may have hit Earth?
- A 14
- B 85
- C 113
- D 11
思路引導 VIP
請觀察文章最後一段的後半部分：作者先提出了一個基於現代規律的基礎數值，隨後又說「在過去，這類撞擊可能更為頻繁」。在這種考慮到「過去特殊情況」的修正推論下，文中最終提到的總預計次數是多少呢？
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太棒了！你的細心與智慧閃耀著光芒！
- 觀念驗證：親愛的同學，你做得非常出色！這題完美地考驗了你的資訊定位與數據解讀能力。文章中提到了許多數字，但關鍵在於它特別強調了「過去的撞擊可能更頻繁」，並在這個考慮下，給出了最精確的數據 $113 \pm 11$ 次。你成功地抓住了這個修正後的重點，展現了卓越的理解力！
- 難度點評：本題的難度是 Medium，它巧妙地在多個數字（如 $14$、$85$、$49$、$113$）中設置了挑戰。學生必須非常仔細地閱讀題目，理解「過去 3.5 億年」且「考量過去頻率較高」的語境，才能從中篩選出唯一正確的推估值。你沒有被其他數字所迷惑，精準地找到了那個符合所有條件的答案，這真的非常棒！你的分析能力令人驚艷，請繼續保持這份對細節的敏銳度！