汽车一、二级维护作业是依据（）的有关规定。
A.汽车维修企业
B.车辆使用说明书
C.市级以上交通行政主管部门
D.汽车运输企业
参考答案：A
请简述施工图预算的基本概念。
Which of the following statements about a monopolist is most accurate A monopolist will:（）
A. earn economic profits in all situations.
B. maximize the average profit per unit sold.
C. sell at the output level where marginal revenue equals marginal cost.
