( Based on the growth rates of large modern reptiles such as ) the Galapagos tortoise and examination of fossils of juvenile dinosaurs, scientists estimate that the larger dinosaurs probably lived to be between 100 and 200 years old. A. Based on the growth rates of large modern reptiles such as B. On the basis of growth rates of large modern reptiles such as C. Based on the growth rates of large modern reptiles like D. On the basis of growth rates of large modern reptiles, like those of E. Based on the growth rates as those of large modern reptiles like 答案是B，错选了A。科学家基于爬行动物的生长率，估计了恐龙的存活时间。科学家做based on的逻辑主语有错吗？麻烦老师讲解。 (Based on account of various ancient writers) , scholars have painted a sketchy picture of the activities of an all-female cult that, perhaps as early as the sixth century B.C, worshipped a godness known in Latin as Bona Dea "the good goddess". A. Based on account of various ancient writers B. Basing it on various ancient writer's accounts C. With accounts of various ancient writers used for a basis D. By the accounts of various ancient writers they used E. Using accounts of various ancient writers 答案是E，还是错选了A。做题时在AE纠结了好久，因为不确定学者作为“基于不同作家的解释”的主语是不是错的，而且感觉基于要比使用的表达更好，尽管可以确定using的主语是学者，但还是把E排除了，麻烦老师讲解。 因为不知道这两道题是犯了什么错误，所以去有道查了based on 的例句，发现人是可以做主语的：Based on the finding, one might predict that the bank should increase its display and budget. 以及 Based on that representation, the district judge denied a motion to dismiss the new comlaint. 麻烦老师讲解这几个题的区别。

讲解

DS：已知9个数的平均数是43，求标准方差 1）最小的那个数是43 2）最大的那个数是43

一个数n的因子有2，3，5，n < 200，求n？ 条件1：4不是他的因子 条件2：9是他的因子

一辆火车走600 miles的路程，一般需要10h；火车中间走了一段速度20 miles的路；接下来是速度60miles的路，问速度60miles走了多久？ 条件1：速度20 miles走了3个小时 条件2：600 miles路程平均速度为56miles

一个数被10r整除，但不被10r+1整除，求r？ 条件1：这个数被25整除不被26整除 条件2：这个数被56整除不被57整除

数学考了一道，本来某一天下午两点水池剩n方水，每小时漏1/4方，每天下午一点会加进去14方，问水池剩m方的时候是星期几几点？

一个长方形长x宽y，能不能比较沿x边卷起的圆柱体体积和y边卷起圆柱体的体积？ 条件1：2x大于y 条件2：x小于3y

一个公司准备给一个地区中大于等于65，并且在当地呆的时间小于等于5年的人，发放谋谋福利，问这部分所占比例？ 条件1：该地区≥65岁的占比（某个值） 条件2：该地区呆的时间≤5年的人占比（某个值）

问x^y是否是odd？ 条件1：x是odd 条件2：可以求出来y是odd

编号1-8的蓝木板放到一个箱子里，编号1-8的红木板放到另一个。每个箱子各抽一块板，问抽到蓝木板和红木板编号一样的几率是多少？ 老师为什么不是 1/64?