7) Yesterday, Cindy re-posted a meme on social media and tagged 3 of her friends. Today, each
of her 3 friends re-posts the meme and tags 3 of their friends. This pattern of re-posting and
tagging 3 friends continues for several days. How many people have re-posted the meme
after 8 days? (Hint: If this is geometric, you should write a formula to help answer the
question)