Question: To send a letter in the mail,
Option 0: write the return address on the front, center of the envelope.  Place the required amount of postage onto the envelope in the top right corner.  Write the destination address in the top left corner.
Option 1: write the destination address on the front, center of the envelope.  Place the required amount of postage onto the envelope in the top right corner.  Write the return address in the top left corner.
Answer: 1