A.0.2~0.4mm B.0.4~0.6mm C.0.6~0.8mm D.小于0.2mm
A.叶轮的形状 B.叶轮的直径大小 C.轮毂的厚度 D.叶片的高度
A.大于0.75mm B.0.65~0.70mm C.0.55~0.60mm D.0.45~0.50mm