user: Question: What is the magnitude with epicenter at Vrancea County, Unknown intensity and which happened at 06:36?
Columns: ['Date', 'Time (UTC)', 'Epicenter', 'Magnitude', 'Depth', 'Intensity']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['October 3, 2004*', '09:02', 'Tulcea County', '5.0 M b', '2km', 'VII (Damaging)']
SQL:

assistant: SELECT "Magnitude" FROM "Table" WHERE "Epicenter" = 'Vrancea County' AND "Intensity" = 'Unknown' AND "Time (UTC)" = '06:36';