No, there are no spaces within hyphenated words. There should only be a space before and after the entire word like all words when you are writing.
No, gift certificate is not a compound or just one word. You just put a space between the two words.
You do not use a hyphen when writing square feet. Using a hyphen would make it one word which should not be the case.
These are two words. There is no hyphen in the concept. In charge means to have leadership in English, so there is no hyphen to connect the two.
No, cleanout is one word.
lifetime is just one word and you don't use a hyphen. (example): Hopefully my parents won't die during my lifetime.
No the word "reevaluation" is one word.
No it is one word: cannonball.
It is foolish to leave a job before finding another one. With the troublesome world economy, it could take a long time to find other employment.
no it does not get a hyphen, cause it is one word.
Before the second one.
You can leave two spaces if you wish but if you do, you must be consistent. I was originally taught to leave two spaces but now only ever leave one.