                                                                                                                  10—4                10—4       —         
      10—5            He4     N14          2    2     7   7           9   9          F18                                         8   9       O17            
    4 ＋   14 →   18 →
  He4＋N14→  F18 →
    17 ＋  1 
   10—5      a           b               c                 
                                                                                    