组成图像矩阵中的基本单元的是（）
A.体素
B.像素
C.元素
D.灰阶
E.视野
参考答案：B
Was it at the school ______ was named after a hero ______ he spent his childhood?
A．which; that
B．where; that
C．that; where
D．which; where
从1994年1月1日起，我国实行（）制，取消外汇分成。
A.外汇收入转汇
B.外汇收入换汇
C.外汇收入结汇
D.外汇收入售汇
