I'm Tom. I have a friend. Her name is Lucy. She is ____.Her favourite food is ____. She is thirsty. She would like some ____ .Her water bottle is ____the table. Look! There is her photo ____the table.
如图,直线y1=kx+b过点A(0,2),且与直线y2=mx交于点P(1,m),则不等式组mx>kx+b>mx-2的解是( )
____: 25 = 25 ; 59 ×9÷ 59 ×9=____;
1.75× 625 +0.76÷ 47 =____; 2520﹣36×42÷27____.
目前,一些地方在公开招聘中,出现了为干部子女“量身定做”招聘条件的事件。此类事件受到谴责是因为( )①祈盼公平,维护正义是人们的共同心愿 ②公平关系到每个人的切身利益③公平总是相对的,要受社会条件的制约 ④ “量身定做”违背公平竞争原则
如图,在三棱锥S﹣ABC中,平面SAB⊥平面SBC,AB⊥BC,AS=AB,过A作AF⊥SB,垂足为F,点E,G分别是棱SA,SC的中点.求证:
一中子与一质量数为A (A>1)的原子核发生弹性正碰.若碰前原子核静止,则碰撞前与碰撞后中子的速率之比为( )