60÷1000×10=____
种子里最重要的结构是胚,胚可以萌发成新的幼体.胚的结构包括( )
根据课文《风》内容填空。
①你听树叶沙沙沙,那是____。
②你看树枝在点头,那是____。
The famous piano teacher ______ Robby as a student only because he said it had always been his mother's dream to hear him play the piano.
Don’t drink all your water ____
用频率为ν的单色光照射某种金属时,逸出光电子的最大动能为EK,已知普朗克常量为h,则该金属的逸出功为____;若改用频率为2ν的单色光照射此种金属时,则逸出光电子的最大动能为____.