“文字是建立在语言基础之上的一种最重要的辅助交际工具。”怎样理解这句话？

为了研究实心圆柱体对水平地面的压力的作用效果与哪些因素有关，某同学用若干个不同的圆柱体竖直放置在水平沙面上，进行了三组实验，并记录了有关数据分别如表一、表二、表三所示．实验时他仔细观察沙面的凹陷程度，并通过比较，发现每一组的凹陷程度都相同，而各组却不同，第一组的凹陷程度最大，第二组其次，第三组最小．

表一（ρ_铜=8.9×10³千克/米³）

实验序号	材料	高度（厘米）	底面积（厘米2）
1	铜	20	10
2	铜	20	20
3	铜	20	30

表二（ρ_铁=7.8×10³千克/米³）

实验序号	材料	高度（厘米）	底面积（厘米2）
4	铁	20	10
5	铁	20	20
6	铁	20	30

表三（ρ_铜=8.9×10³千克/米³）

实验序号	材料	高度（厘米）	底面积（厘米2）
7	铜	10	10
8	铜	10	20
9	铜	10	30

（1）分析比较实验序号1、2、3（4、5、6，或7、8、9）的数据及观察到的现象，可得出的结论是：当圆柱体材料的密度和高度相同时，压力的作用与底面积______（选填“有关”或“无关”）．

（2）分析比较实验序号______的数据及观察到现象，可得出的初步结论是：当圆柱体的高度相同时，材料的密度越大，压力作用效果越显著．

（3）分析比较实验序号1与7（或2与8、或3与9）的数据及观察到的现象，可得出的初步结论是：______．

（4）甲、乙、丙三位同学进一步综合分析比较表一、表二、表三中的数据及观察到的现象．

甲同学计算了每次实验中材料密度与圆柱体高度的乘积，得出结论：当材料密度与圆柱体高度的乘积相同时，压力作用效果相同，乘积不同，压力作用效果不同；

乙同学计算了每次实验中材料密度与圆柱体高度的差值，由此得出结论：当材料密度与圆柱体高度差值越小时，压力作用效果越显著；

丙同学计算了每次实验中材料密度与圆柱体高度的比值，得出结论：材料密度与圆柱体高度的比值越大，压力作用效果越显著．

请判断，甲同学的结论是______，乙同学的结论是______，丙同学的结论是______．（均选填“错误”、“不完整”或“正确”）

取已部分风化的碳酸钠晶体10.7克，溶于水制成饱和溶液，逐滴加入足量的饱和澄清石灰水使其完全反应，然后过滤．将所得的固体经洗涤、烘干后高温灼烧至重量不再减少为止，得白色固体2.8克．计算这种碳酸钠晶体的结晶水失去的百分率是多少？

分析薄膜吸声结构的吸声机理和主要吸声特性。

刑事诉讼的终止

A study released a little over a week ago, which found that eldest children end up, on average, with slightly higher IQ’s than younger siblings, was a reminder that the fight for self-definition starts much earlier than freshman year. Families, whatever the relative intelligence of their members, often treat the firstborn as if he or she were the most academic, and the younger siblings fill in other niches: the wild one, the flirt.

These imposed caricatures, in combination with the other labels that accumulate from the sandbox through adolescence, can seem over time like a miserable entourage of identities that can be silenced only with hours of therapy. But there’s another way to see these alternate identities: as challenges that can sharpen psychological skills. In a country where reinvention is considered a birthright, many people seem to treat old identities the way Houdini treated padlocked boxes: something to wriggle free from, before being dragged down. And psychological research suggests that this ability can be a sign of mental resilience, of taking control of your own story rather than being trapped by it.

The late-night bull sessions in college or at backyard barbecues are at some level like out-of-body experiences, allowing a re-coloring of past experience to connect with new acquaintances. A more obvious outlet to expand identity—and one that’s available to those who have not or cannot escape the family and community where they’re known and labeled—is the Internet. Admittedly, a lot of the role-playing on the Internet can have a deviant quality. But researchers have found that many people who play life-simulation games, for example, set up the kind of families they would like to have had, even script alternate versions of their own role in the family or in a peer group.

Decades ago the psychologist Erik Erickson conceived of middle age as a stage of life defined by a tension between stagnation and generativity-a healthy sense of guiding and nourishing the next generation, of helping the community. Ina series of studies, the Northwestern psychologist Dan P. McAdams has found that adults in their 40s and 50s whose lives show this generous quality—who often volunteer, who have a sense of accomplishment—tell very similar stories about how they came to be who they are. Whether they grew up in rural poverty or with views of Central Park, they told their life stories as series of redemptive lessons. When they failed a grade, they found a wonderful tutor, and later made the honor roll; when fired From a good job, they were forced to start their own business.

This similarity in narrative constructions most likely reflects some agency, a willful reshaping and re-imagining of the past that informs the present. These are people who, whether pegged as nerds or rebels or plodders, have taken control of the stories that form their identities.

In conversation, people are often willing to hand out thumbnail descriptions of themselves:" I’m kind of a hermit." Or a talker, a practical joker, a striver, a snob, a morning person. But they are more likely to wince when someone else describes them so authoritatively.

Maybe that’s because they have come too far, shaken off enough old labels already. Like escape artists with a lifetime’s experience slipping through chains, they don’t want or need any additional work. Because while most people can leave their family niches, schoolyard nicknames and high school reputations behind, they don’t ever entirely forget them.

Psychologists seem to believe that if adults want to remake their identity, they need to（）

A. tell their psychologists very similar stories about themselves

B. command the identity-forming factors themselves

C. quit their jobs and start their own business

D. hire a wonderful tutor to get themselves into the honor roll