Final answer:
A letter can be used as a form of argument by providing facts and information to an audience, or by making a more personal appeal to another person.
Step-by-step explanation:
A letter can be used as a form of argument in different ways. One way is to provide the audience with facts and information specifically for them, supporting the argument being made. For example, if someone is arguing for stricter laws on climate change, they can use a letter to present scientific evidence and data to convince the reader of the urgency and importance of the issue.
Another way a letter can be used as an argument is to make a more personal and intimate appeal directly to another person. In this case, the writer is making their case or expressing their views to someone they have a connection with or want to influence. For instance, a letter to a local politician expressing concern about a specific policy or legislation can be a form of argument, where the writer is seeking to persuade the politician to take a specific action.
In summary, a letter can be used as a form of argument to provide facts and information to an audience, display a more personal appeal to another person, and ultimately persuade or convince the reader to support the writer's views or take action on a specific issue.
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