This depends on the specific rules you are using. In most cases they are left out, but you may have to follow a particular style book.
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.
From PM today to PM tomorrow is a duration of 24 hours. This period includes the entire span of one full day. If you consider it from a specific PM time today to the same PM time tomorrow, the count remains 24 hours.
From seven o'clock AM to eight o'clock PM is a total of 13 hours. This period includes the full hours from 7 AM to 7 PM, which is 12 hours, plus one additional hour from 7 PM to 8 PM. Thus, the total is 13 hours.
From 7:30 PM to 6:00 AM is a total of 10 hours and 30 minutes. This period includes the entire night and part of the morning.
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.
The term "AM to PM" typically refers to a 12-hour period, ranging from midnight (12:00 AM) to noon (12:00 PM) or from noon (12:00 PM) to midnight (11:59 PM). In a standard work context, if you mean a full workday from 9 AM to 5 PM, that equates to 8 hours of work. However, if you're referencing the entire period from AM to PM (midnight to midnight), that totals 24 hours.
If they're both on the same date, then they mark a period of 21/2 hours.
7 PM to 4 AM GMT is the same period as 2 PM to 11 PM EST.
From PM today to PM tomorrow is a duration of 24 hours. This period includes the entire span of one full day. If you consider it from a specific PM time today to the same PM time tomorrow, the count remains 24 hours.
AM is in the morning until 11:59 and PM is in the evening until 11:59
The covalent atomic radius of carbon is 70 pm; oxygen has 60 pm and lithium 140 pm.