下列关于债券特征的描述，错误的是（）。 ["安全性是指债券持有人的权益相对固定，且一定可按期收回投资","偿还性是指债券有规定的偿还期限，债务人必须按期向债权人支付本息","流动性是指债券持有人可以按自己的需要和市场情况灵活的转让债券","收益性是指债券能为投资者带来一定的收入，即债券投资的报酬"]
矿床有何特征？
简述面向对象法的优点。
Your network contains a Windows Server 2008 R2 server that functions as a file server. All users have laptop computers that run Windows 7. The network is not connected to the Internet. Users save files to a shared folder on the server. You need to design a data provisioning solution that meets the following requirements： èUsers who are not connected to the corporate network must be able to access the files and the folders in the corporate network. èUnauthorized users must not have access to the cached files and folders. What should you do？（） ["Implement a certification authority （CA）. Configure IPsec domain isolation.","Implement a certification authority （CA）. Configure Encrypting File System （EFS） for the drive that hosts the files.","Implement Microsoft SharePoint Foundation 2010. Enable Secure Socket Layer （SSL） encryption.","Configure caching on the shared folder. Configure offline files to use encryption."]
“燃烧通论”中提出，物体只有在（）存在时才能燃烧。 ["氢","氮","氧","二氧化碳"]
现存唐传奇大部分收录在《太平广记》里，鲁迅所辑录的《（）》，廓清了明清书商“妄制篇目，改题撰人”的流弊，是一个较好的辑本。
