A:that were we…thi
B:that we were…that
C:if were we …thi
D:if we were…that
“黄梅时节家家雨,青草池塘处处蛙”描述了我国哪个地区的景象( )
如果△ABC∽△DEF,且对应高之比为2:3,那么△ABC和△DEF的面积之比是____.
给出下列函数:①y=2x;②y=﹣2x+1;③y=2x(x>0);④y=x2(x<1),其中y随x的增大而减小的函数是( )
吃水果、蔬菜时要注意的事项是( )