I had been a step-mother for six years, and with my husband，I had watched his young children growing into teenagers. Although they lived mostly with their mother, they spent a lot of time with us. O
若实数x、y、m满足|x﹣m|＜|y﹣m|，则称x比y接近m． （1）若x2﹣1比3接近0，求x的取值范围； （2）对任意两个不相等的正数a、b，证明：a2b+ab2比a3+b3接近；
2011年5月26日，人民日报评论员发表评论员指出：执政着要在众声喧哗中倾听“沉没的声音”。上述观点与下列名言的寓意最贴近的是（ ） A．
铅蓄电池的两极分别为Pb、PbO2，电解质溶液为H2SO4，电池放电时时的反应为Pb+PbO2+2H2SO4=2PbSO4+2H2O，下列对电池放电时的分析正确的是 A．Pb为正极被氧化
First impressions are the most lasting. After all, you never get ________ second chance to make _______ first impression. A. a; the B. the; the C. a; a
Bob Harris was a weatherman at a small television station. He worked for twenty years and during those twenty years, he felt that his life was boring. Every day, he studied the weather and tried to
短周期主族元素X、Y、Z、W原子序数依次增大，X原子最外层有6个电子，Y是至今发现的非金属性最强的元素，Z在周期表中处于周期序数等于族序数的位置
某一地点，以北是北半球的高纬度，以南是北半球的中纬度，以东是西半球，以西是东半球，该点位于 A．经度1800，北极圈 B．经度18
