During halogen test, sodium fusion extract is boiled with concentrated HNO₃ to

In the flame test of a mixture of salts, a green flame with blue centre was observed. Which one of the following cations may be present?

During the qualitative analysis of salt with cation y²⁺, addition of a reagent (X) to alkaline solution of the salt gives a bright red precipitate. The reagent (X) and the cation (y²⁺) present respectively are :