读短文，判断下列句子的正(√)误(×)。

      Hello, my dear friends! I'm a dress. I have many brothers and sisters. We all live in a happy family-a

wardrobe (衣柜). Come and meet my family members (家庭成员)! Look! This is a jacket. That is a skirt.

These are sweaters. We often sing and dance together. We all love each other.

( ) 1. The dress has many brothers and sisters.

( ) 2. They all live in a wardrobe.

( ) 3. Coats are the dress's family members.

( ) 4. These clothes often sing and dance together.

已知点A（1，1）在二次函数y=x²-2ax+b的图象上．

（1）用含a的代数式表示b；

（2）如果该二次函数的图象与x轴只有一个交点，求这个二次函数的图象的顶点坐标。