本题目来源于试卷: Physics Unit30: Nuclear Physics and Radioactivity，类别为 Generic Physics
[单选题]
The atomic number and mag7 6es9qvs d qlqj69m8ss number for calcium 39 arllc: fa 0 9z8meu.o.1(enz9afo cmk p7e 20 and 39, respectively. How many neutrons are in o9zczpe llc.ma8e7nk 91 u0moa( ff. :one atom?
A. 1
B. 19
C. 20
D. 39
参考答案: B
本题详细解析:
暂无
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Post time 2024-1-22 01:01:29