汽车匀速行驶,由甲地到乙地时速度为v1,由乙地返回甲地时速率v2则往返全程的平均

题型:选择题

问题:

汽车匀速行驶,由甲地到乙地时速度为v1,由乙地返回甲地时速率v2则往返全程的平均速率是(  )

A.

V1+V2
2

B.

v1v2
v1+v2

C.

v1+v2
v1v2

D.

2v1v2
v1+v2
考点:平均速度和瞬时速度的区别
题型:选择题

细菌明胶液化试验原理是()

A.某些细菌产生胞外酶,能使明胶分解为蛋白质

B.某些细菌产生胞内酶,能使明胶分解为蛋白质

C.某些细菌产生胞外酶,能使明胶分解为氨基酸

D.某些细菌产生胞内酶,能使明胶分解为氨基酸

E.某些细菌产生胞外酶,能使明胶分解为明胶酸

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施工过程中,如果发包人需要撤换工程师,应至少于易人前()天以书面形式通知承包人,并继续履行前任作出的书面承诺。

A.7

B.14

C.28

D.30

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试比较歧腔吸虫和前后盘吸虫的各自形态特点及生活史

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在公安领域大量使用的数据结构模型是()

A.网状数据库模型

B.关系数据库模型

C.层次数据库模型

D.树状数据库模型

题型:选择题

There is a marked difference between the education which every one gets from living with others and the deliberate educating of the young. In the former case the education is incidental; it is natural and important, but it is not the express reason of the association. (46) It may be said that the measure of the worth of any social institution is its effect in enlarging and improving experience, but this effect is not a part of its original motive. Religious associations began, for example, in the desire to secure the favor of overruling powers and to ward off evil influences; family life in the desire to gratify appetites and secure family perpetuity; systematic labor, for the most part, because of enslavement to others, etc. (47) Only gradually was the by-product of the institution noted, and only more gradually still was this effect considered as a directive factor in the conduct of the institution. Even today, in our industrial life, apart from certain values of industriousness and thrift, the intellectual and emotional reaction of the forms of human association under which the world’s work is carried on receives little attention as compared with physical output.

But in dealing with the young, the fact of association itself as an immediate human fact, gains in importance. (48) While it is easy to ignore in our contact with them the effect of our acts upon their disposition, it is not se easy as in dealing with adults. The need of training is too evident and the pressure to accomplish a change in their attitude and habits is too urgent to leave these consequences wholly out of account. (49) Since our chief business with them is to enable them to share in a common life we cannot help considering whether or not we are forming the powers which will secure this ability. If humanity has made some headway in realizing that the ultimate value of every institution is its distinctively human effect we may well believe that this lesson has been learned largely through dealings with the young.

(50) We are thus led to distinguish, within the broad educational process which we have been so far considering, a more formal kind of education—that of direct tuition or schooling. In undeveloped social groups, we find very little formal teaching and training. These groups mainly rely for instilling needed dispositions into the young upon the same sort of association which keeps adults loyal to their group.

(50) We are thus led to distinguish, within the broad educational process which we have been so far considering, a more formal kind of education—that of direct tuition or schooling.

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