What the question there is nun
Electron configuration
an element A has 3 shells and has 3 valence electrons
so electron configuration of A: 1s², 2s², 2p⁶, 3s², 3p¹
will tend to lose 3 electron to form a cation: A³⁺
a. Nitrate of A
A(NO₃)₃
b. Chloride of A
ACl₃
c. Oxide of A
A₂O₃
