采用二层胎体增强材料时，上下层不得（ ）铺设。
A. 平行
B. 相互垂直
C. 逆向
D. 以上皆可
体增强材料短边搭接宽度不得小于（ ）mm。
A. 80
B. 70
C. 60
D. 50
After listening to the conversation above, choose the best answer.What are the speakers doing ?
A. Discussing a new project
B. Chatting about their work
C. Participating in a job interview
D. Arranging a sales meeting
Choose the best answer.What does the man's present job involve?
A. Selling audio products
B. Designing speakers
C. Launching new video games
D. Supervising company management
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