In relation to company law, explain what is meant by:

(b) a public listed company. (5 marks)

柴油机同一活塞上的活塞环的开口位置应互相错开，如有四道环，应按（）进行装配。

A.一180°二90°三180°四

B.一90°二°180°三180°四

C.一180°二180°三90°四