题目内容

X线产生中，电子从阴极射向阳极所获的能量，决定于下面的哪个因素（）

A. X线管灯丝加热电压
B. 两极间的管电压
C. 靶物质的原子序数
D. 管电流
E. 阴极灯丝的焦点大小

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单位预留银行签章变更，认真审核单位提交的申请变更公函是否写明（）

A. 变更原因
B. 新签章启用日期
C. 并加盖与原预留银行签章有明显区别的新签章
D. 是否在公函上注明必须交回盖有旧签章的空白重要凭证种类、数量、编号等资料等

电梯选层后，操纵盘上的选层箭头同时点亮，各层厅外层楼指示灯点亮。

A. 正确
B. 错误

当发动机处于同一转速时，随着飞行高度提高，压气机的增压比值会（）

A. 增加
B. 减小
C. 不变
D. 忽增忽减

You work as an ASP.NET Web Application Developer for SomeCompany. The company uses Visual Studio .NET 2010 as its application development platform.You create an ASP.NET Web site using .NET Framework 4.0. Only registered users of the company will be able to use the application. The application holds a page named UserAccount.aspx that enables new users to register them to the registered users„ list of the company. The UserAccount page hold numerous TextBox controls that accept users personal details， such as user name， password， home address， zipcode， phone number， etc. One of the TextBox controls on the page is named ZipCode in which a user enters a zip code. You must ensure that when a user submits the UserAccount page， ZipCode must contain ﬁve numeric digits. What will you do to accomplish this？（）

A. Use RangeValidator.
B. Use RegularExpressionValidator
C. Use RequiredValidator
D. Use CompareValidator
E. Use RequiredFieldValidator