题目

His uncle      inTianjin since he came back to China . A. has lived      B. had lived      C. lived         D. is living 答案：A在平面直角坐标系中，我们把横坐标和纵坐标都是整数的点称为格点，则到坐标原点O的距离为10的格点共有（ ）个． A．4 B．6 C．8 D．12