Read the example letter below, and answer the question that follows. June 14, 2015 1234 Maplewood Lane Sunnydale, MN 55003 Dear Courtney, I hope you are doing well, and that your recent move to Sunnydale went smoothly. We all miss you greatly, but are excited for you to begin your new career in wildlife photography. I am writing to ask if you would consider writing a letter of reference for my application to the summer photography program at the local community college. When applying to the program, I immediately thought of you as a potential reference. As my former supervisor, you have directly observed my passion for photography, and my willingness to learn more about the field. I believe that my time working with you at the photography studio was an excellent first step towards my future career in the field. The letter of reference will enable me to continue my growth and experience in photography. I hope that you will consider writing the letter of reference, and I truly appreciate your consideration. Regards, Samantha Carlotta

What is the above an example of?

friendly letter
business letter
letter of reference
request letter