Passage 1

21.【答案】B。解析：推断题。根据第二段最后一句话“The Arabs took the new numbers and made improvements that quickly led to advances in technology.” 以及最后一段的内容可推断出在很久以前阿拉伯人拥有很先进的技术。故答案选B。

22.【答案】A。解析：细节题。根据第一段最后一句 “In Roman numeral, it comes out like this MCMLXXXIV. Imagine how difficult it would be for a school pupil to remember it!” 可知罗马数字比阿拉伯数字更复杂，学起来更难。故答案选A。

23.【答案】D。解析：细节题。根据第二段第2句话 “This is probably because they got the original idea a long time ago from India.” 故答案选D。

24.【答案】A。解析：推断题。根据第二段第三句There were no printed newspapers or scientific magazine then, so mathematics traveled along the same routes that silk did, as businessmen sold and bought goods. 可知阿拉伯与印度人进行交易。故答案选A。

25.【答案】C。解析：推断题。根据文章最后一段最后一句话“In fact, cities outside the Arab world did not reach the same level of social development until centuries later.” 可知阿拉伯比其他国家更先进。故答案选C。