近年来，我国各级政府不断加大对农业和农村的投入，对种粮农民实行直接补贴，不断加大

权责发生制与收付实现制的区别在于（）。

A.权责发生制根据权责关系的实际发生和影响期间来确认会计期间的收支和损益

B.收付实现制完全以款项的实际收付日期为基础来确定收入和费用的归属期

C.与权责发生制相比，收付实现制能够更加准确地反映特定会计期间真实的财务状况和经营成果

D.与收付实现制相比，权责发生制能够更加准确地反映特定会计期间真实的财务状况和经营成果

E.权责发生制是与收付实现制并存的会计基础

The following questions present a sentence, part of which or all of which is underlined. Beneath the sentence, you will find five ways of phrasing the underlined part. The first of these repeats the original; the other four are different. If you think the original is best, choose the first answer; otherwise choose one of the others.

These questions test correctness and effectiveness of expression. In choosing your answer, follow the requirements of standard written English; that is, pay attention to grammar, choice of words, and sentence construction. Choose the answer that produces the most effective sentence; this answer should be clear and exact, without awkwardness, ambiguity, redundancy, or grammatical error.

To be a great salesman requires p personal skills, the ability to think fast, and demands a can-do attitude.（）

A. requires p personal skills, the ability to think fast, and demands

B. requires p personal skills, the ability to think fast, and

C. requires p personal skills, demands the ability to think fast, and

D. requiring p personal skill, an ability to think fast, and demands

E. demands p personal skills, an ability to think fast, but with

Greeting me with a nod, she said in a soft voice,"Hi, you must be Gori. " Then, she _____  the music

and lookedover at Dad.    [ ]

A. turned on                  

B. turned down    

C. played                    

D. enjoyed

已知方程2|x|-k=kx-3无负数解，那么k的取值范围是（）。

A.-2≤k≤3

B.2＜k≤3

C.2≤k≤3

D.k≥3或k≤-2

E.以上结论都小正确

试述系统的基本概念。