Prudence, indeed, will dictate that governments long established should not be changed for light and transient causes . . how does the author appeal to ethos here? (apex btw)

An appeal to ethos is an appeal to credibility or moral character. It is a type of persuasive argument, which means that it attempts to convince an audience of a particular argument. In this case, the author is telling us that governments that have a long standing tradition are usually managed by "prudent" (careful, wise) people, which means that they do not often change for unimportant or temporary reasons.

it creates a visual picture of the man.

it conveys what the scene sounds like.

it describes the actions of the boy.

it reveals the poet’s opinion of the characters.

it encourages readers to care for the characters.