If you are reading an opinion about whether parents should monitor the music their teens are listening to, you are probably reading which of these?

Editorials are articles that express the editor's opinion or beliefs on a topical issue. Hence, if you are reading an opinion about whether parents should monitor the music their teens are listening to, you are reading an editorial article.

The other options are incorrect because News article tells current or recent news of general interest or of a specific topic, and often include accounts of witnesses to the event; A feature article is about stories, fictional or nonfictional, of human interests that focus on a special event, place or person in great detail, and Exposé is the type of article that reveals a hidden truth, often through investigation, about someone or something, which may come off as shocking or surprising to the reader.

onto a large boat, and mark the water level that the boat sinks to. then, take the elephant out and put a bunch of marked weights onto the boat until it reaches the same water level. add up the masses of the weights to get the weight of the elephant.

a is is the correct answer