Hyphen is a punctuation mark which has a symbol that look like this ( - ), this is used at the end of a line when a word must be divided or to link the parts of a compound word or phrase.
path-oecologist
between the word
If you're using the phrase as an adjective (example "I hate the end-of-the-year audit!") then it will definitely need the hyphens. Otherwise, the hyphens are incorrect.
I advise against hyphens in that particular case.
Hyphens not needed
Yes it should be hyphenated.
There are no hyphens in the word ago.
Hyphens are always used in compound numbers like twenty-one.
It would be text. However, if there are just numbers and a hypen or hyphens, then the hyphens could be a minus sign and you would get a formula if you put an equals sign before it.
You use hyphens to make compound words that are not recognizable in common usage.
It changes the hyphens into end dashes.
If you're using the phrase as an adjective (example "This easy-to-use remote is great!") then it will definitely need the hyphens. Otherwise, the hyphens are incorrect.