“黄梅时节家家雨，青草池塘处处蛙”反映的是我国哪一地区的美景

已知x，y，z均为正数，且|x﹣4|+（y﹣3）2+ =0，若以x，y，z的长为边长画三角形，此三角形的形状为____．

  The students were having their chemistry（化学）class. Miss Li was telling the children what water was like. After that, she asked her students, “What's water?" No one spoke for a few minutes．Miss Li asked again，“Why don't you answer my question？Didn't I tell you what water is like？”
Just then a boy put up his hand and said，"Miss Li，you told us that water has no color and no smell．But where to find such kind of water？The water in the river behind my house is always black and it has a bad smell．"Most of the children agreed With him．
“I'm sorry，children．”said the teacher，"Our water is getting dirtier and dirtier．That's a problem”．

图形都是由同样大小的棋子按一定的规律组成，其中第①个图形有1颗棋子，第②个图形一共有6颗棋子，…，则第⑦个图形棋子的个数为（  ）