A. No, both features within the cohort are measured differently. 

When looking a the time parameter of "months", it is based on the logic of a "week" being classified as 7 days. So in this case, 1 "month" would be 4 weeks or 28 days. 

When looking at the "days" time parameter, you can set the exact amount of days you want the cohort builder to look back to. 

Note: Both options are great tools for use when defining your audience.