PM or p.m. same fro AM or a.m
If they're both on the same date, then they mark a period of 21/2 hours.
It's neither, 12 noon and 12 midnight are just that although there are a lot of illiterates in positions where they should know better!)
It was 3 am when Frank got home.
Habit, and convention. We all have to speak the same language if we're going to communicate. Personally, I prefer the 24 hour clock; so 1 PM is 13:00, and 9 PM is 21:00. Of course, I did spend 21 years in the Navy, and we used the 24-hour clock exclusively. But for talking to civilians in the US, you have to use the 12 hour clock with AM and PM.
PM or p.m. same fro AM or a.m
PM
PM or p.m. same fro AM or a.m
3 PM until 6 PM
The end of a sentence always needs a period.
The correct way to write the phrase is "PM role." with a period after "PM" as it is an abbreviation for Project Manager.
If they're both on the same date, then they mark a period of 21/2 hours.
7 PM GMT is 3 PM Eastern Standard Time. 4 AM GMT is 11 PM Eastern Standard Time.
The covalent atomic radius of carbon is 70 pm; oxygen has 60 pm and lithium 140 pm.
AM is in the morning until 11:59 and PM is in the evening until 11:59
Rubidium has the largest atomic size in period 5 of the periodic table.
Lunch time is typically considered to be during the daytime, which would make it before noon, so it falls under the AM (ante-meridiem) period.