A:12,+∞)
B:(﹣∞,12
C:(0,+∞)
D:1,+∞)
⑴This is a photo of Hainan. ____
⑵I got to school by car yesterday.____
⑶Beijing is in the north of China.____
⑷The mountains are really beautiful.____
⑸I went to England last year.____
灰兔和白兔杂交,F1全是灰兔,F1雌雄个体相互交配,F2中有灰兔、黑兔和白兔,比例为9∶3∶4,则 ( )
①推动产业结构优化升级和技术创新
②不断增强国有经济的控制力、影响力
③加大财政转移支付力度,给予税收减免
④加强科学管理,优化资源配置
如图,一个四棱锥的底面为正方形,其三视图如图所示,则这个四棱锥的体积为( )
下列变化中分子一定发生改变的是( )