根据以下木材的截面尺寸,指出中方为()。 ["60mm³60mm;","80mm³80mm;","30mm³30mm;","100mm³300mm。"]
投诉处理中心回复客户的时限要小于或等于几个小时?() ["2","4","6","8"]
促胰液素对胃运动及分泌的影响依次为() ["增强,增多","增强,减少","抑制,抑制","减弱,增多","没有影响"]
大众传播学
根据以下木材截面尺寸,指出薄板为()。 ["15mm³100mm;","20mm³150mm;","50mm³50mm;","30mm³240mm。"]
预防空气预热器泄露的措施有哪些?