把一个图形先沿着一条直线进行轴对称变换,再沿着与这条直线平行的方向平移,我们把这样的图形变换叫做滑动对称变换.在自然界和日常生活中,大量地存在这种图形变换(如图1).结合轴对称变换和平移变换的有关性质,你认为在滑动对称变换过程中,两个对应三角形(如图2)的对应点所具有的性质是( )
A:对应点连线与对称轴垂直
B:对应点连线被对称轴平分
C:对应点连线被对称轴垂直平分
D:对应点连线互相平行
回答问题(简答)。
Lucy is my good friend. She is eleven years old. She is a student. She likes singing. She has a nail pet. Her name is Kitty. Look, Lucy's singing and the cat is dancing. Lucy wants to be a singer when she grows up.
Lucy's mother is a nurse. She works in a hospital. She likes shopping. She usually buys a lot of beautiful clothes at weekends.
比7多4的数是____。
9+3=( )
89 79 69 ____ 49 ____
40 35 30 ____ 20 ____
厨房中的下列物质与水混合后,不能形成溶液的是( )