考专升本难度大吗?四川省

有效循环血量指（　　）

A.维持正常代谢所需血量

B.包括存于肝、脾和淋巴窦及停滞于循环中的血量

C.全身血容量

D.单位时间内通过心血管系统进行循环的血量

E.以上都不是

Sometimes I scratch my head when I read about the government′s efforts to improve schools:new standards and tests to be applied,strict teacher evaluations,and threats of school closures and?job losses．They frighten the school employees,not to mention the students．Instead of making people?unable to solve problems or try new ideas—which is what fear does to us—research on school reform?strongly suggests that policy-makers should encourage school leaders to take a more humane?approach．In their study on the reform efforts of twelve Chicago public schools,Bryk and Schneider
found that enabling positive social relationships between the adults was the key to successful school?improvement and that trust was at the heart of those relationships．
Trust in schools comes down to one thing:psychological safety or safety to speak one′s mind,to?discuss with openness and honesty what is and isn′t working,to make collective decisions．
Yet this kind of safety doesn′t come easily to schools．According to Bryk and Schneider,the?adults in school rely on each other to do their jobs correctly and with integrity(正直)．The challenge?is that our expectations are very diverse based on our unique backgrounds．
At one school where I taught,each teacher had different expectations about how much extra?effort teachers should put into their work—a big difference between the teachers who left after the?last bell and those who worked into the evening．And when expectations are unconscious or?unspoken,it becomes impossible for others to live up to them．
We also make assumptions about the intentions behind a person′s behavior．As we all know,assumptions are often wrong．For example,parents and teachers may think the principal made a?particular decision based on his career advancement rather than what′s best for the students．If we?don′t feel psychologically safe to question our assumptions and expectations,trust flies out the?window and our relationships suffer．


What is meant by trust in school?《》（）

A.Freedom to express one's views．
B.Extra effort teachers put into their work．
C.Independence of the teachers in schools．
D.Unconscious and unspoken expectations．

设函数y=x^3，则y′=__________．