Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
Which Right ascension (J2000) has a Constellation of mensa, and an NGC number larger than 2171?

### Inputs:
table_name: table, columns: ['NGC number', 'Object type', 'Constellation', 'Right ascension ( J2000 )', 'Declination ( J2000 )']

### Response:
SELECT Right ascension ( J2000 ) FROM table WHERE Constellation = mensa AND NGC number > 2171