This individual project is simple: after reading Technical Communication chapter 14, and attending especially to our authors' advice on "you-centered" writing (the "you attitude"), address exercises 1-3 on p. 387 of our Technical Communication text. You need not fill out and submit full-blown Audience and Use profile sheets, but you would indeed do well to make casual notes about audience expectations and attitudes in your document planning process.
Design a professional-caliber letterhead for each letter, and note that each should be at least 250 words in length in the body text of the letter (excluding addresses, etc.), but no more than 400 words.
Submit all three letters as separate documents (Word or PDF) to the appropriate D2L dropbox.