Teresa is a software saleswoman. Her base salary is $1600, and she makes an additional $80 for every copy of History is Fun she sells. Let P represent her total pay (in dollars), and let N represent the number of copies of History is Fun she sells. Write an equation relating P to N. Then use this equation to find her total pay if she sells 28 copies of History is Fun. Equation: Total pay if Teresa sells 28 copies: $ X 0=0 S