Social Studies Chapter 5 Study Guide Test TOMORROW!! barter - to trade goods and services without using money. opportunity cost - what you give up when you make a choice. Ex: You want both a CD and a jacket but you only have enough for one. The item that you don’t choose is your opportunity cost. goods - products that people want and need, and that can be touched or held. scarcity - not having enough resources to provide all the things people want. budget - a plan for how to spend or save money Goods Chocolate Bar Flowers Clothing Shoes Groceries Toys Games Services Teeth cleaning/Dentist Wellness exams/Doctor House cleaning Lawn mowing Dog walking Firefighting Police work Tutoring Babysitting Needs are those things that you cannot survive without: food, water, clothing, shelter, etc. Wants are those things that you can survive without but may enjoy having: bikes, game systems, fancy cars, toys, etc.