ChatGPT on the velocity of light in a vacuum

I thought ChatGPT would be able to tell me the velocity of light in a vacuum, but it only half managed it, saying the answer was approximate, which it is actually defined to be 299,792,458 metres per second.

What is the velocity of light in a vacuum?

The velocity of light in a vacuum is approximately 299,792,458 meters per second, denoted by the symbol "c". This is a fundamental physical constant and is considered to be the maximum speed limit for anything in the universe, according to the theory of relativity.

Are you sure your answer is correct? I thought c was defined in the SI units to be exactly 299,792,458 meters per second.

(Oops, I copy/pasted ChatGPT's 299,792,458 meters per second. The length should be spelt metres, not meters. This is not an English/American spelling issue - it's an SI unit, and should be spelt only one way.)
You are correct. The value of the speed of light in a vacuum, denoted by the symbol "c", is defined to be exactly 299,792,458 meters per second in the International System of Units (SI). This definition was adopted in 1983 by the General Conference on Weights and Measures and has been in use ever since. Thank you for bringing this to my attention and I apologize for any confusion my previous response may have caused.