444 Willow Drive Tokyo, Japan 100-0001 April 30, 2024Dear Mr. Johnson,I wanted to write and thank you for all the advice you gave me during high school. Your encouragement helped me get into university, and I'm loving my studies now. I often think about your history classes - they sparked my interest in the world. How's retirement treating you?Sincerely, RyanWhat is the main purpose of the letter written by Ryan?