30.
In a certain code language,
M & N means βM is the son of Nβ,
M @ N means βM is the brother of Nβ,
M $ N means βM is the father of Nβ,
M # N means β M is the mother of Nβ.
Based on this, how is E related to A, if βA # B $ C @ D & Eβ?