如图所示,用等大反向的力F和F′压住两块木板,中间夹着一个重量为G的立方体金属块,它们一起处于静止状态.则( )
— How was your stay in Hong Kong?
—________. And it was a pity that I couldn't stay there longer.
《氾胜之书》中写道:“杏始华荣,辄耕轻土、弱土。望杏花落,复耕……草生,有雨泽,耕重蔺之。土甚轻者,以牛羊践之,如此则土强。”此耕作方法( )
在数列{an}中,a1=2,2an+1=2an+1,则a101的值为 ( )