迈克尔逊—莫雷实验的结果表明（） A.以太是不存在的 B.以太风是不存在的 C.以太

Police have appealed for         to the accident. [ ]

A. on lookers              

B. viewers

C. people

D. witnesses

Paul, CFA, heads the research department of a large brokerage firm. Paul has supervisory responsibility over 25 analysts. If Paul delegates some supervisory duties, which statement best describes his responsibilities based on the Standards of Professional Conduct（）

A. Paul is not responsible for those duties he has delegated to his subordinates.

B. Paul’s supervisory responsibilities only apply to analysts with the CFA designation.

C. Paul retains supervisory responsibility for all subordinates despite his delegation of some duties.

某运输公司有7个车队，每个车队的车都多于4辆且型号相同，要从这7个车队中抽出10辆车组成一运输车队，每个队至少抽1辆车，则不同的抽法有多少种？

简述数字签名的基本原理?

有人说，经济建设是所有工作的中心，所以应该培育中小学生的经济意识而不是民族精神。这种观点（）

A.肯定了经济建设的极端重要性，正确

B.揭示了当前教育中存在的弊端，正确

C.忽视了培育民族精神的必要性，错误

D.抹杀了民族精神在教育中的作用，错误