肉酥依据中国国家标准（CNS）规定，豆粉含量不得超过原料肉重的（）。 ["5％","10％","15％","20％"]
AAA authentication login做什么用？
在32×2.5Gb/s系统，关于固定衰减器和可调衰减器的使用方法正确的是（） ["一般情况下，每个放大器的前端都放置一个可调衰减器。","在分波器的前端也应放置可调衰减器。","TWC的输出端一般要放置固定衰减器。","RWC的接收端一般放置固定衰减器。"]
表象
With PGP， which of the following entity signs a users’s public key？（） [" The sender of the message."," The receipient of the message."," The sender’s administrator who provides the sender with the PGP program."," A third party that belongs to what’s often known as "web of trust"， that can verify the relationship between the user and the key."," The vendor of the PGP program."]
简述隋唐时期商业发展的主要成就。
