已知某制药厂年产木糖醇1000吨，其制造原料玉米心在当地市场无法满足供应，必须从东北地区供应，因此运杂费增加50元/吨，该工厂木糖醇生产线预计剩余寿命还有10年，折现率为10%，所得税率为25%，试求该生产线的经济性贬值额。
Refer to the exhibit. STP has been implemented in the network. Switch SW_A is the root switch for the default VLAN. To reduce the broadcast domain， the network administrator decides to split users on the network into VLAN 2 and VLAN 10. The administrator issues the command spanning-tree vlan 2 root primary on switch SW_A. What will happen as a result of this change？（） All ports of the root switch SW_A will remain in forwarding mode throughout the reconvergence of the spanning tree domain.。 Switch SW_A will change its spanning tree priority to become root for VLAN 2 only.。 Switch SW_A will remain root for the default VLAN and will become root for VLAN 2.。 No other switch in the network will be able to become root as long as switch SW_A is up and running.。
为了保持物体在吊运中平稳，吊钩中心线与物体重心必须在（）位置上。 同一水平位置。 同一垂直线。 相同角度。
卫藏
Your web application requires the ability to load and remove web files dynamically to the web container’s filesystem. Which two HTTP methods are used to perform these actions？（） PUT。 POST。 SEND。 DELETE。 REMOVE。
下列属于《易制毒化学品管理条例》规定管制的化学品是（）。
