A.一級,500mm; B.二級,600mm; C.一級,600mm; D.二級,600mm
A.600~800mm,500mm; B.800~1000mm,500mm; C.500~600mm,600mm; D.600~800mm,600mm
A.5min,1/2; B.5min,1/4; C.10min,1/3; D.10min,1/4