CT设备硬件的基本结构不包括（）
A.扫描机架系统
B.扫描检查床
C.X线管及数据收集系统
D.计算机及阵列处理机
E.激光相机
参考答案：E
－My parents our home for a few hours when I arrived. I didn’t meet them.
－You could call them if you wanted to know where they were.
A．have been away from
B．had been away from
C．had left
D．had gone
瓦斯的化学性质不活泼，且不溶于水。（）
