What are two benefits of control plane policing？（） ["protection against denial of service （DoS） attacks at infrastructure routers and switches"," protection against known worm attacks in routers and switches","quality of service （QoS） control for packets that are sourced from the data plane of Cisco routers and switches","quality of service control （QoS） for packets that are destined to the control plane of Cisco routers and switches","quality of service （QoS） control for packets that are destined to the data plane of Cisco routers and switche"]
循环式索道分为哪几种？
下列哪种试剂是测定水耗氧量的常用的氧化剂？（） ["过氧化氢","过硫酸胺","高锰酸钾","草酸钠"]
在测定食品中挥发性酸的过程中，所采用的蒸馏方法为（）。 ["常压蒸馏","减压蒸馏","加压蒸馏","水蒸气蒸馏"]
碰碰船、峡谷漂流等船只，必须在限制的（）内行驶，不得混杂在一起。 ["速度；","深度；","水域；","方向。"]
细菌分类的依据：（）、（）。
