Why does Mr. Smith invite Chinese friends to visit his country?
A.Because he wants to have a chance to be host and return some kindness.
B.Because he wants to discuss the business with the Chinese friends.
C.Because he wants to promote their company's products.
第3题
A.道钉孔周围腐朽严重,无处改孔,不满足持钉和保持轨距要求
B.通裂严重,影响共同受力
C.桥枕内部腐朽严重
D.已经过削平、挖槽等作业,但累计深度小于80㎜
第7题
A.标准断面桥枕因腐朽、挖补、削平和挖槽累计深度超过70mm
B.道钉周围腐朽严重,无处改孔,不能满足持钉及保持轨距
C.桥枕内部严重腐朽
D.通裂严重,影响共受力
第9题
A.劈裂严重,最长裂缝达一节护木的1/2,且穿过螺栓孔
B.螺栓周围木质严重腐朽,木材强度显著降低,不起保持桥枕位置的作用
C.护木内部严重腐朽
D.有劈裂发生,最长裂缝大于一节护木 的1/6,但不超过1/2
为了保护您的账号安全,请在“上学吧”公众号进行验证,点击“官网服务”-“账号验证”后输入验证码“”完成验证,验证成功后方可继续查看答案!