人和动物的学习有本质的区别，人类的学习主要是在有目的的人类（）中进行的，并采用了特定的（）。 ["社会活动；工具","科学研究；方法","生产实践；语言","改造自然；工具"]
总体数据库设计的原则是什么？
第四代计算机
与机械台班折旧费计算有关的项目有（）。 ["残值率","贷款利息系数","大修理费","耐用总台班","安拆费"]
Which of the following is a characteristic of a data center core？（） [" Server-to-server traffic always remains in the core layer."," The recommended practice is for the core infrastructure to be in Layer 3."," The boundary between Layer 2 and Layer 3 should be implemented in the aggregation layer."," The Cisco Express Forwarding hashing algorithm is the default， based on the IP address andLayer 4 port."," Core layer should run BGP along with an IGP because iBGP has a lower administrativedistance than any IGP."]
申请换领《快递业务经营许可证》的，应当什么时间提出申请？
