user: Question: If the founding university is in Washington, D.C., what was the founding date?
Columns: ['Letters', 'Organization', 'Nickname', 'Founding Date', 'Founding University', 'Type']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['ΔΛΦ', 'Delta Lambda Phi', '"DLP", "Deltas\'", or "Lambda Men"', '1986-10-15', 'Washington, D.C.', 'Fraternity']
SQL:

assistant: SELECT "Founding Date" FROM "Table" WHERE "Founding University" = 'Washington, D.C.';