细菌性痢疾的主要病变部位是()
A.回肠末端
B.乙状结肠与直肠
C.升结肠
D.降结肠
E.空肠
参考答案:B
下列关于DVD光盘的叙述中,不正确的是( )。
A.DVD光盘是可以采用多面多层信息记录技术 B.DVD光盘的直径与CD光盘相同 C.DVD光盘的道间距小于CD光盘的道间距 D.DVD光盘使用的激光波长与CD光盘相同
Cost of quality is the total cost of all efforts to achieve product/service quality,and includes all work to ensure conformance to requirements.All of the following are costs that are incurred EXCEPT ().
A.cost of poor quality
B.opportunity cost
C.external failure cost
D.appraisal cost