工程经济学是（）。 ["是工程技术学科与经济学科的交叉学科","是研究工程技术实践活动经济效果的科学","是概率统计科学","就是以工程项目为主体，如何提高经济效益的科学"]
Which two statements are true about the digital audio in a VoIP network？（） ["Standard encoding techniques create an uncompressed digital data rate of 4000 bps.","Standard encoding techniques create an uncompressed digital data rate of 8000 bps.","Standard encoding techniques create an uncompressed digital data rate of 64，000 bps.","Voice quality is not a concern if compression is not used.","Two methods of quantization are linear and logarithmic.","Two methods of compression are u-law and a-law."]
Which routing protocols can be used within the enterprise network shown in the diagram?（） ["RIP v1","RIP v2","IGRP","OSPF","BGP","EIGRP"]
填写肝素生产工艺流程中的空格（A~G）
利用下表资料，计算人民币汇率的综合汇率变动率。
道德社会化
