Here putting food in a man's mouth represents feeding him. AT: "is to put food in his mouth" or "is to feed him" (See: [[rc://en/ta/man/translate/figs-metonymy]])
The author uses this rhetorical question to emphasize that a wise person does not have any more lasting benefits than a fool. This question can be written as a statement. AT: "it seems the wise person has no advantage over the fool." (See: [[rc://en/ta/man/translate/figs-rquestion]])
The author uses this rhetorical question to emphasize that a poor man does not have any more lasting benefits than someone else. This question can be written as a statement. AT: "The poor man has no advantage even if he knows how to act in front of other people." (See: [[rc://en/ta/man/translate/figs-rquestion]])