两个相似三角形对应中线的比2:3,周长的和是20,则两个三角形的周长分别为( )
A:8和12
B:9和11
C:7和13
D:6和14
The Earth is sick
The Earth was clean and beautiful.
Now some parts are
红花有12朵,黄花的朵数是红花的2倍,蓝花的朵数比黄花的3倍还多1朵,三种花一共有几朵?