英版海图（额定光力射程）上某灯塔的灯质为Fl4s49m24M，测者眼高为16m。则能见度为6n mile时，该灯塔灯光的最大可见距离为 __（）

A.大于20nmile

B.小于20nmile

C.大于23nmile

D.小于23nmile

A.大于22nmile

B.小于22nmile

C.大于20.9nmile

D.小于20.9nmile

A.19.3nmile

B.23.0nmile

C.24.2nmile

D.25.0nmile

A.10.5nmile

B.15nmile

C.16.7nmile

D.无法确定

A.大于14nmile

B.小于14nmile

C.大于16.7nmile

D.小于16.7nmile

A.大于22nmile

B.小于22nmile

C.大于25.1nmile

D.小于25.1nmile

A.大于18nmile

B.小于18nmile

C.大于16.7nmile

D.小于16.7nmile

A.21.4nmile

B.27.2nmile

C.28.6nmile

D.25.0nmile

A.25n mile

B.23n mile

C.24n mile

D.20n mile

A.每隔5s闪光2次，射程为10nmile

B.每隔5s闪光1次，2次10秒

C.灯高11米，射程为10nmile

D.灯高10米，射程为11nmile

A.光力射程

B.额定光力射程

C.地理射程

D.或B