下列选项中能提高传感器性能的是（）。
A.平均技术
B.差动技术
C.稳定处理
D.屏蔽和隔离
参考答案：A, B, C, D
句型转换。
1. They were studying in the room at that time. (就画线部分提问)
_________ _________ they _________ in the room at that time?
2. He was away from school because he helped his father at home. (就画线部分提问)
_________ _________he away from school?
槟榔驱绦虫的成人一日用量是
A．1～3gB． 3～6gC．6～15gD．15～30gE．60～120g
