Yes it should be hyphenated: co-worker.
Swiss should be capitalized; coworker should not be capitalized.
Can you, or should you? You can hyphenate it if you're moving between lines in a paragraph and need to break up the word. You shouldn't hyphenate it normally.
McCarthy should not be hyphenated.
not required
A hyphen is not required.
Yes it should be hyphenated.
Yes it should be hyphenated.
Yes, hyphenate by-laws.
According to the sources I've found on a quick search, you should hyphenate 'coauthor', i.e., it would better be: "co-author".
If a coworker is being electrically shocked, do not touch them, and shut off the power.
IT ALL DEPENDS WHAT THIS COWORKER HAS DONE. IF HE HAS BROKEN THE LAW, THEN YOU SHOULD.. IF IT'S JUST SOME PETTY OFFICE THING, THEN WORK IT OUT BETWEEN YOU.
you should modify the problem