设某传输码序列为0-20+2+2000-2-2-2，该传输码属于（）。
A.相关码
B.差分码
C.双相码
D.绝对码
参考答案：A
Mrs. Green wants to buy that kind of cloth because she___________ that the cloth__________ very well.
A．has been told; washes
B．is told; is washed
C．has been told; is washed
D．is told; is washed
路基的填土，最好采用( )。
A．细砂 B．粉砂土C．粗填D．黏性土
