In the body of the letter.
Formal language is the most appropriate language when writing a business letter.
Letter
You would write a proposal, an offer of an agreement or contract.
One would use formal language in a business letter because it is a formal means of communication. When writing a business letter, one wants the tone to be professional. Formal language can help the writer to achieve this.
it depends if you are writing a complaint it would be the title with out dear and if a friendly letter dear is correct
Formal language is the most appropriate language when writing a business letter.
letter of inquiry
Letter
You would write a proposal, an offer of an agreement or contract.
Report
If you are writing on an envelope, your name appears as the return address. In a business letter, your name and address would appear above the addressee's followed by a salutation and the letter text.
The most formal kind of functional writing would be formal letters. This type of letter would be used in circumstances dealing with business matters or even when writing to a stranger.
One would use formal language in a business letter because it is a formal means of communication. When writing a business letter, one wants the tone to be professional. Formal language can help the writer to achieve this.
In the U.S., if you are going to do it by yourself (there are companies who offer to prepare business plans for entrepreneurs, but I don't have any experience with them), a good place to start would be the website of the U.S. Small Business Administration, which covers the writing of a business plan clearly and in great detail.
if you wrote a letter to the school principle then it would be a business letter Example: their address and yours Dear Mrs. (or Mr.) Name I am writing to you on account of your student body. We would appreciate it if you would think about changing the school's menu. We have noticed alot of repetitive lunches and would be very pleased if you would add more changes to the school menu as soon as possible. Thank you, your student body Writing a letter like this one it must be formal and strait to the point. In other words a business letter and always refer to the person as Mr. or Mrs. and then their last name.
it depends if you are writing a complaint it would be the title with out dear and if a friendly letter dear is correct
Provide the purpose of the letter (APEX)