(来学网)X线机房主防护方向铅当量应达到
  • A.
    (来学网)1mmPb
  • B.
    (来学网)2mmPb
  • C.
    (来学网)3mmPb
  • D.
    (来学网)4mmPb
  • E.
    (来学网)5mmPb