试述射线探伤时如何在底片上辩认焊接缺陷？
Your network contains two Active Directory forests. One forest contains two domains named contoso.com and na.contoso.com. The other forest contains a domain named nwtraders.com. A forest trust is configured between the two forests. You have a user named User1 in the na.contoso.com domain. User1 reports that he fails to log on to a computer in the nwtraders.com domain by using the user name NA\User1. Other users from na.contoso.com report that they can log on to the computers in the nwtraders.com domain. You need to ensure that User1 can log on to the computer in the nwtraders.com domain. What should you do（） Enable selective authentication over the forest trust.。 Create an external one-way trust from na.contoso.com to nwtraders.com.。 Instruct User1 to log on to the computer by using his user principal name （UPN）.。 Instruct User1 to log on to the computer by using the user name nwtraders\User1.。
常见的尿管型有哪些？
产生汽水共沸的原因可能有（） 锅水质量不合格有油污或者含盐浓度过大。 锅水成酸性。 长期不能进行排污或排污间隔时间过长，排污量小。 用汽量过小。
某工程项目的案卷封面标注的保管期限是长期：长期是指工程档案需保存（）。 40年以上。 30年以上。 20年以下。 等于该工程的使用寿命。
党的十八大提出，到2020年实现全面建成小康社会宏伟目标，即包括（）
