Abdul's seventh grade class is going on a field trip to a history museum. There are x students and y teachers going on the trip. Tickets for students are $10 each and tickets for teachers are $20 each. The history museum gave the class 20% off as part of a group promotion.
Pick all the expressions that represent the total cost of the field trip
1. 0.2($10x + $20y)
2. $10x + $20y - 0.2($10x + $20y)
3. $10x + $20y - 0.2($10x) - 0.2($20y)
4. $10x - 0.2($10x) + $20y - 0.2($20y)