They had trade routes and sold to the people of the lands.
It is first when it comes to creating an environment because after primary succession occurs, then the environment is destroyed, the succession that comes after that is secondary succession.
If it's only regarding the invention of a specific dental equipment, it'll be to inform. the student is preparing to share their knowledge on the dental drill.
to persuade is usually the purpose when there's a question or an argument being raised, and in this case, it doesn't sound like anyone would be against dental drills. dental drills is also a fairly dry topic, so it's doubtful that the student would be aiming to entertain. it isn't a demonstration because the student likely isn't giving a step by step how to in regards to using a dental drill.
