确诊慢性胃炎的主要依据是：（） ["年龄","X线钡餐检查","大便潜血试验","HP检查","胃镜及胃粘膜活检"]
下列选项中是专业排版软件的是（） ["freehand","coreldraw","photoshop","pagemaker"]
凯恩斯认为，人们持有货币的动机有（）、预防动机和（）。
Why will a switch never learn a broadcast address?（） [" Broadcast frames are never sent to swiches."," Broadcast addresses use an incorrect format for the switching table."," A broadcast address will never be the source address of a frame."," Broadcasts only use network layer addressing."," A broadcast frame is never forwarded by a switch."]
自然经济
等级评价法
