a+a2-6a+9=3，
则a+|a-3|=3，
只有当a≤3时，a+3-a=3，
故a的取值范围是a≤3．
The building _____ in our school is for us teachers. Though there’s noise most of day, we still feel happy about it .
A．built
B．has been built
C．being built
D．to be built
已知正方形ABCD四条边与圆O内切，而正方形EFGH是圆O的内接正方形。已知正方形ABCD的面积为1，则正方形EFGH的面积是( )。
(E)
(E) 