Q. I can’t find anywhere in CMOS the correct procedure for punctuation at the end of rhetorical questions. A question mark seems out of place and an exclamation point, which CMOS does mention, seems gratuitous. Here are two such rhetorical questions from my forthcoming book:
The question for any owner or manager was, however, how much revenue are those live commercials bringing into the station.
The bigger question would be, could Crist and Johnson hold on to the station.
Will a period suffice for those?
A. CMOS 6.69 (“Direct and Indirect Questions”) is probably what you’re looking for. Your sentences do require question marks, but it might be better to reword them as statements with periods:
The question for any owner or manager was, however, how much revenue those live commercials are bringing into the station.
The bigger question would be whether Crist and Johnson could hold on to the station.
See CMOS 6.42 for related advice.