Among the statements (a) - (d), the correct ones are :
(a) Decomposition of hydrogen peroxide gives dioxygen.
(b) Like hydrogen peroxide, compounds, such as KCIO₃, Pb(NO₃)₂ and NaNO₃ when heated liberate dioxygen.
(c) 2-Ethylanthraquinone is useful for the industrial preparation of hydrogen peroxide.
(d) Hydrogen peroxide is used for the manufacture of sodium perborate.

In comparison to the zeolite process for the removal of permanent hardness, the synthetic resins method is :

The temporary hardness of a water sample is due to compound X. Boiling this sample converts X to compound Y. X and Y, respectively, are :

The metal that gives hydrogen gas upon treatment with both acid as well as base is :