一颗红色尖晶石正确的定名为() ["红宝石尖晶石","尖晶石","红色尖晶石"]
人面感觉有风,树叶微响,风向标转动,表示的风是()。 ["A、无风","B、轻风","C、微风","D、和风"]
按广告的目标,可将广告分为:(). ["A、机构广告","B、原始需求广告","C、信息性广告","D、说服性广告","E、提醒性广告","F、选择性广告"]
层流时,截面上各点速度的平均值u等于管中心处最大速度的()倍。 ["1/2","1/3","1/4","1/5"]
东陵石中的鳞片状、星点包体是() ["铬云母","蓝铁线","赤铁矿"]
三种印迹技术的名称分别是()、()和()。