单项选择题
A.19.3nmile B.23.0nmile C.24.2nmile D.25.0nmile
A.12.7nmile B.17.0nmile C.18.8nmile D.19.8nmile
A.测者眼高和灯塔灯高 B.灯塔灯高和灯光强度 C.灯光强度和气象能见度 D.灯塔灯高、灯光强度、地面曲率和地面蒙气差