皮皮学，免费搜题
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搜题
【简答题】
Download the Homework-news headlines 2. Read aloud the news headlines and understand them well. 3. Choose three headlines, read them fluently and at the same time record your reading (just record three headlines, not all; One headline one audio recording. at the beginning of your recording, you should say "I am going to read headline number 1 or number 2.... so that it is easier for me to find it"). 4. Upload your reading of these three headlines to Xuexitong before 17 March.
拍照语音搜题，微信中搜索"皮皮学"使用
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皮皮学刷刷变学霸
举一反三
【简答题】下列不属于轻于空气航空器的是( )
【单选题】如下图所示，甲、乙、丙、丁是四个体积形状相同而材料不同的球，图中所示是把它们投入水中后静止不动时的情况，它们中密度最小的球是： [ ]
A.
甲
B.
乙
C.
丙
D.
丁