.如图所示，线段AC和BD交于O点，且OA=OC，AE∥FC，BE=FD，则图中共有 对全等三角形.
对下列细胞分裂模式图的分析，正确的是（ ） A．分别具有甲、乙、丙、丁细胞的生物个体，属于4个不同的物种 B．4个细胞的染色体上都不含染色
For many years scientists have said that the earth is getting warmer. Now they have found something new-hot cities! In the southern US, they have found that cities become very hot in s
平面直角坐标系中，抛物线交轴于A、B两点（点A在点B左侧），与轴交于点C，点A、C的坐标分别为（-3,0），（0,3），对称轴直线交轴于点E,点D为顶点. （1
There is some doubt among people __________ $750 is too much for an iPhone 6 A. that B. whether C. what D. if
17. We got to the airport early,_____missing our flight. A. in case of B. instead of C. for fear of D. in search of
下列数剧中与实际相符的是 A．中学生脚的长度为50cm B．中学生的体重为50N C．人体的密度约为1.0×103kg/m3 D．人在正常呼吸时肺内
