蛋白质稀释液中加入双缩脲试剂后，颜色是（）
A.浅蓝色
B.砖红色
C.绿色
D.紫色
参考答案：A
六（1）班今天的出勤率是96%，缺席2人，六（1）班有学生______人．
We went through a period _______ communications were very difficult in the rural areas.
A, which B, whose C, in which D, with which
