When excess $$\text{KMnO}_4$$ is added to concentrated $$\text{H}_2\text{SO}_4$$, an oily green colored covalent compound Y is formed. Which of the following statements is or are true for the above reaction?

A

Compound Y is formed by a dehydration reaction

B

In compound Y Mn is octahedrally surrounded by oxygen atoms

C

Y is the highest oxide of Manganese

D

Compound Y has an $$\text{Mn} - \text{O} - \text{Mn}$$ bridge