测量从湖北到北京的距离，用______作单位合适．
测量从湖北到北京的距离，用 千米作单位合适．
故答案为：千米．
最大理论分辨力，在数值上为
A．4λ
B．2λ
C．λ
D．1／2λ
E．1／4λ
The chairman asked me to ________the report, because he didn't want to speak for too long at this meeting.
A．cut out
B． cut in
C．cut off
D．cut down
