Billie jean has $120 to spend and wants to buy either a new amplifier for her guitar or a new mp3 player to listen to music while working out. both the amplifier and the mp3 player cost $120, so she can only buy one. this illustrates the basic concept that- trade can make everyone better off.- people face trade-offs.- rational people think at the margin.- decisions made at the margin are not particularly important.

People face trade-offs.

Explanation:

A trade off is a giving up of one thing in return for another. All of the alternatives that we give up when we choose one course of action over the other.

Is a sacrifice of one good to purchase or produce another good. Must be maid because when a resource is used to produce one good, that same resource cannot be used to produce another.

Is an alternative that you face if you decide to do one thing rather than other. There is a choose to use resources in one way and not the other.

answer; i believe a ( newsletter ) should be sent;