Anderson specializes in corn and Brooks in wheat:
Total:               60                30
Terms of trade:
*Specialization allows individuals to take advantages of their differences, allocates resources for maximum output, and fosters excellence in skills and technology*

Indifference analysis:

Decision-making agents (could be family, firm, government bureau) have choices,  well-defined preference functions, and an opportunity set (range of options available i.e. income). Operative behavior is optimization.