Composition of the nuclei of two atomic species X and Y are given as under, help Aravind to answer the following:
 
 
X
Y
Z
Protons \(8\) \(8\) \(9\)
Neutrons \(8\) \(10\) \(9\)
  
i. Relation between Y and Z
 
Y and Z have the same .
They have different .
Therefore, Y and Z are .
 
ii. Relation between X and Y
 
X and Y have the same .
They have different .
Therefore, X and Y are .
 
iii. Which isotope is used in the treatment of cancer?