A 4-column table with 2 rows. Column 1 has entries Spent, Earned. Column 2 is labeled Day 2 with entries 7, 16. Column 3 is labeled Day 3 with entries 12, 22. Column 4 is labeled Day 4 with entries 9, 18. Juan ran the lemonade stand for 3 more days after his first day profit of $12. Each day, he used the money from sales to purchase more lemons, cups, and sugar to make more lemonade. The table shows how much he spent and earned each day.

What is the expression needed to find his total earnings?

What were his total earnings?