已知△ABC中，∠A=∠B+∠C，则△ABC的形状是（　　）

     May 10th is Meg’s birthday. She gets a gift from her sister. It is a new coat .The coat is very beautiful and she feels very happy.

     One day, Meg finds that a button(纽 扣) of her coat is lost. She looks for the button everywhere, but she can’t find it. The next day, she doesn’t wear that coat to school and feels sad all day. After school, she goes to the clothes shops and wants to buy that kind of clothes. But she doesn’t find it. She feels very disappointed.

     Meg tells her sister about that, and her sister says, “We can change all the buttons. Then the buttons will be the same.” The coat is beau  tiful again and Meg feels happy again.