None!
There should be no spaces within a hyphenated word. For example: ex-husband.Note in the example that there are no spaces before and after the hyphen.
In the case of a hyphenated word, none. In the case of a hyphen used as a dash, once before and once after.
There shouldn't be any spaces in a hyphenated word.
The number of spaces that follow an abbr. is one.
Yes, there is. Often, after a hyphenated word has been used for a very long time and is used by many people, the hyphen will be eliminated. Email is an example of this. Originally the word was e-mail.
Not usually. Many compound words do begin with hyphenation, and co-operate is an example. Without the hyphen, it might be pronounced "cooper eight". Once the word is sufficiently well recognised, the hyphen is used less and less, so that many people nowadays write "cooperate".
There aren't any spaces after the apostrophe in a contraction (did you see what I did?)
It normally requires a hyphen: window-pane, but many hyphenated words are having their hyphens dropped, so in another 20 years it might be a genuine compound word.
none
There should be one space.
One space follows a period after an initial.
One space is sufficient.