Scott sends an email to 3 people and each of those people will send the email to 3 more people, and so on. Which expression shows the number of people that will receive the email after the fourth round?

Thats where they was ported and the fields that noone really knew much about needed tended, so they put slaves out there do free work and huge profits and so on the north decided to hold its own and was more different way of survival did not have same climate conditions to afford protecting slaves from winter so expenses be diff from south