Unless otherwise specified, assume that all matrices in these exercises are n × n. Determine which of the matrices in Exercises 1–10 are invertible. Use as few calculations as possible. Justify your answers.
ECO Ch. 1 Book Notes (Answers) The total cost of carrying out n units of an activity divided by n is the activity’s average cost. A cost that is beyond recovery at the moment a decision is made is a sunk cost. A positive economic principle is one that predicts how people will behave. Economic models are useful in explaining & predicting behavior even if people aren’t consciously using those models to make decisions. The CostBenefit Principle states that an individual or society should only take an action if, and only if the extra benefits from taking the action are at least as great as the extra costs. The Scarcity Principle states that although we have boundless needs and wants, the resources available to us are lim