A.5B.3C.2D.1
A.防護成熟齡B.數(shù)量成熟齡C.更新成熟齡D.自然成熟齡
A.經(jīng)營不虧不盈B.過熟,經(jīng)營虧損C.成熟,應立即采伐D.未成熟,可繼續(xù)經(jīng)營