(来学网)当加速器治疗床步进距离的误差为2mm时,剂量不均匀性可达
  • A.
    (来学网)51%
  • B.
    (来学网)41%
  • C.
    (来学网)31%
  • D.
    (来学网)20%
  • E.
    (来学网)60%