“_______” is the height above the ground or water of the base of the lowest layer of cloud below 6000m covering more than half sky.
A.roof
B.VFR Top
C.VMC
D.Ceiling
正确答案是D
“_______” is the height above the ground or water of the base of the lowest layer of cloud below 6000m covering more than half sky.
A.roof
B.VFR Top
C.VMC
D.Ceiling
正确答案是D