user: ### NOW ANSWER:
Question: Which Right ascension (J2000) has a Constellation of Mensa, and an NGC number larger than 2171?
Columns: ['NGC number', 'Object type', 'Constellation', 'Right ascension ( J2000 )', 'Declination ( J2000 )']
Types: ['real', 'text', 'text', 'text', 'text']
Sample row: [2129.0, 'Open cluster', 'Gemini', '06h01m06s', '°19′20″']
SQL:

assistant: SELECT "Right ascension ( J2000 )" FROM "Table" WHERE "Constellation" = 'Mensa' AND "NGC number" > 2171.0;