金字塔位于埃及尼罗河下游西岸,建于公元前27世纪,是一种方锥形建筑物.十分有趣的是,自然数1,2,3,4…也可以写成下面的金字塔: 同学们看一看、想一想,这座自然数金字塔中的数的排列有哪些规律?请把你的新发现填在下表中.(表述要清楚、准确、简练) 序号 规律 ① 每行最右边的数都是该行行数的平方. ② ③ ④
【单选题】根据下列文章,请回答 51~65 题。 The Development of Rubber Here is the story of rubber. From the earliest time it was common knowledge _________ (1) the Peruvians that when a cut was made in the outside skin of a ...