It should be hyphenated.
Yes
You should hyphenate well nourished and well developed IF followed by a noun - i.e., "well-nourished and well-developed man" or "well-nourished and well-developed patient". If the noun is before these, then you would not hyphenate - i.e., "The patient is well nourished and well developed". This would also be true for the following: "well-healed scar" or "the scar is well healed". Answer provided by a medical transcriptionist with 18 years experience.
Yes it should be hyphenated.
Yes it should be hyphenated: well-liked.
It should be hyphenated when it's an adjective.
No. Well above is not hyphenated.
No, well above average is not hyphenated.
It should be hyphenated when it is being used as an adjective.
Well-to-do is a hyphenated word. The direction west-northwest is hyphenated.
Yes it should be hyphenated.
Yes, it should be hyphenated.