72.12 個半值層與 15 個半值層的屏蔽比較,前者光子穿透率是後者的幾倍?
(A)3 倍
(B)8 倍
(C)15 倍
(D)100 倍
答案:登入後查看
統計: A(72), B(1593), C(32), D(11), E(0) #3065957
統計: A(72), B(1593), C(32), D(11), E(0) #3065957