define the following in simple words: Trade-off Consequences Adam Smith Invisible Hand Theory Marginal utility Marginal cost Marginal benefit Marginal Decision Making TINSTAAFL (There Is No Such Thing as A Free Lunch)

Sure! Here are simple definitions for each of those terms:

**Trade-off**: A trade-off is what you give up when you choose one thing instead of another. For example, if you decide to spend your money on a concert ticket, you might have to give up buying a new video game.

**Consequences**: Consequences are the results or effects that come from an action or decision. They can be good or bad. For example, studying hard may lead to good grades, which is a positive consequence.

**Adam Smith**: Adam Smith was a thinker from the 18th century who is often called the father of economics. He wrote a famous book called "The Wealth of Nations," where he talked about how markets work and the importance of free trade.

**Invisible Hand Theory**: The Invisible Hand Theory, introduced by Adam Smith, suggests that individuals pursuing their own interests in a market can lead to good outcomes for society as a whole, like better products and prices, even if that's not their intention.

**Marginal utility**: Marginal utility is the extra satisfaction or benefit you get from consuming one more unit of something. For example, eating one more slice of pizza might make you happier, but the happiness you get from that second slice may be less than the first.

**Marginal cost**: Marginal cost is the additional cost of producing one more unit of a good or service. For example, if a factory makes one more toy, the marginal cost would be how much it costs to make that toy.

**Marginal benefit**: Marginal benefit is the additional advantage or satisfaction you gain when you consume one more unit of something. It helps you decide if what you’re getting is worth the cost.

**Marginal Decision Making**: Marginal decision making involves comparing the extra benefits and extra costs of a choice to decide whether it's worth it. For example, deciding whether or not to study for one more hour based on how much extra you might learn.

**TINSTAAFL (There Is No Such Thing as A Free Lunch)**: This saying means that everything has a cost, even if it seems free. For example, if someone offers you a free lunch, someone else is paying for it, or it might come with strings attached.