Hello!
I am using R for the first time to analyze a dataset for a psychology project. I have 8 dependent measures and need to find the average between each distinct dependent measure's items. The only problem is (1) a few of the items within my dependent measures need to be reverse coded and (2) some dependent measures have sub measures. So, does anyone (A) know the line of code to reverse code specific items within a measure (all my items are numeric, I tried using the package 'car' but R is telling me it is outdated) and (2) create an average for a single dependent measure while still including sub measures?
I have searched the internet for about an hour and a half and am still having no luck 
I am an amateur R user, please explain in layman's terms.
Any feedback is appreciated! 