将下列图片和句子配对。
①What do you need? ____ A. I like the red dress.
②Drink some water, Mum. ____ B. Thank you.
③What do you like?____ C. I need a red dress.
④Smell the orange. ____ D. It's winter.
⑤ What season is it?____ E. It's nice.
圆周率的推算在当代可谓突飞猛进。早在一千多年前,第一个在世界上将圆周率的数值准确到小数点后第七位的数学家是( )
下列四幅地图的图幅大小相同,其中内容最详细的是( )
在平面直角坐标系xoy中,已知△ABC三个顶点的坐标分别为.A(-1,2),B9-3,4),C(-2,9)(1)画出△ABC;(2)画出△ABC绕点A顺时针旋转900后得到的△AB1C1,并求出CC1的长.