Final answer:
An informal style of writing is appropriate in personal essays or letters to friends, whereas a formal style is required in lab reports, history exams, court depositions, résumés, newspaper articles, and job applications.
Step-by-step explanation:
An informal style of writing is appropriate in letter to a friend or personal essay because the purpose is to express personal thoughts and emotions in a casual manner. In these types of writing, the use of contractions, colloquial language, and a friendly tone is acceptable. However, in lab reports or history exams, it is important to use a formal style of writing, presenting information in a clear, objective, and professional manner. For court depositions or résumés, a formal style of writing is necessary to maintain clarity and professionalism. Similarly, newspaper articles or job applications require a formal style to convey information accurately and maintain credibility.
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