In my specific case I want to abbreviate the word section. I abbreviate the singular case to sec. and hope that's correct. I have no idea, however, how to abbreviate sections.
Is it secs? Is it sec.s? Or is it secs.?
The same goes for words such as chapter.
I couldn't find the answer on this site. I did find about abbreviations with mutliple words (e.g. PhDs). I found answers on specific time units (e.g. hours is hrs) but I don't know if this is the case for my question with any noun.