题目

给试管里的粉末物质加热时,以下操作不正确的是                      (   ) A.未说明用量时取固体只要盖满试管底部  B.必须使用试管夹,且手拿住试管夹的长柄 C.加热时,试管必须与桌面成45度角倾斜 D.加热的试管要冷却后放到试管架上 答案:CLast night a hotel caught fire and the whole building ________. Which is wrong?A.burned downB.burned upC.was burned downD.was destroyed
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