Quant - Multiple Regression question, equation, market, natural

former

I have a question as how natural log is applied if one of the independent variable is $, e.g. Market size, sales etc.
In CFAI, question 4 (page 412), book value is C$900MM, and natural log in the regression equation as per the answer, is ln(900,000).
Whereas in question 3 (page 411), market cap is $100MM, and natural log applied as per the answer, is ln(100). Anybody know how to apply ln if $ is one of the independent variable?

Thanks in advance.

eoin

It doesn't matter. Either way works.