AP stylebook says the correct form is a.m. p.m.
No. You put only one period.
No.
Yes.
How many days does the month of September have? Enter the number, and put a period after it.:
How many days does the month of September have? Enter the number, and put a period after it.:
You put a period at the end of the sentence to indicate that the sentence has ended.
Do you put a period after a stated when it is abbreviated in an address?
No. You put only one period.
put the patch on the Sunday after you start your period
no matter what you usually have to put a period after an apostrophe because it's the end of a sentence.
Yes there should be a period.
At the end of this sentence we had to put a period.
Yes there should be a period.
No you don't.
put it outside.
you put a period after an interrogative sentence
We put the period after the word Mr because it's an abbreviation for Mister.