Find the cardinal number for the set. {8,10,12,...66}?

I honestly don't know how to answer the question. Since the definition if a cardinal number is "A Cardinal Number is a number that says how many of something there are", I have some ideas that might work though...

66 divided by 2 is 33. 33 subtract 7 is 26. Therefore, the cardinal number is 26.

Or, the cardinal number might be 66. I don't know.

I suggest maybe paying attention in class when this stuff is being taught.