AD258机器打印复印时文字不规则变淡() ["驱动板故障","激光故障","显影仓内有异物进入","转印辊接触不良"]
注意的两个特点是() ["指向性和集中性","指向性和选择性","调节性和集中性","选择性和集中性"]
设计调查问卷的问题,其形式有哪些?
每位经济舱旅客可以携带一件重()公斤的随身携带物品上飞机。 ["A.3","B.4","C.5","D.6"]
AD166复印出现规律的两条粗线,打印正常,造成的原因是() ["CCD故障","扫描架钢丝磨损","衔接钢丝的白色轮子中的轴承磨损","反光镜装反"]
DNS的中文全称为()。