user: Question: What is the total enrollment at the school that has the nickname of the fightin' blue hens?
Columns: ['School', 'Location', 'Founded', 'Affiliation', 'Enrollment', 'Nickname', 'Primary conference']
Types: ['text', 'text', 'real', 'text', 'real', 'text', 'text']
Sample row: ['University of Delaware', 'Newark, DE', 1743.0, 'Public', 19067.0, "Fightin' Blue Hens", 'Colonial Athletic Association ( D-I )']
SQL:

assistant: SELECT "Enrollment" FROM "Table" WHERE "Nickname" = 'fightin'' blue hens';