预制构件制作模具质量验收中，底模平整度的允许误差为（） ±1mm。 ±2mm。 ±3mm。 ±4mm。
辅助燃烧室在开工时是用来直接加热（） 原料油。 加入的催化剂。 主风。 雾化蒸汽。
Refer to the exhibit.The two connected ports on the switch are not turning orange or green. What would be the most effective steps to troubleshoot this physical layer problem？（） Ensure that the Ethernet encapsulations match on the interconnected router and switch ports.。 Ensure that cables A and B are straight-through cables.。 Ensure cable A is plugged into a trunk port.。 Ensure the switch has power.。 Reboot all of the devices.。 Reseat all cables.。
A Cisco router is booting and has just completed the POST process. It is now ready to find and load an IOS image. What function does the router perform next?（） It checks the configuration register.。 It attempts to boot from a TFTP server.。 It loads the first image file in flash memory.。 It inspects the configuration file in NVRAM for boot instructions.。
物流是（）从（）向（）的（）过程。GB/T规定其英文表示形式是（）。
结构建模分（）建模两种方法
