1. One of the key themes of this course is that any time someone has to make a continuous choice about how much to produce or consume, the optimal decision is to set marginal benefit equal to marginal cost. (a) Explain why setting marginal benefit equal to marginal cost is the optimal solution. Your explanation should be understandable to someone who does not know calculus and has not taken intermediate microeconomics. (b) Provide two specific instances discussed in the course where a MB = MC type decision rule applies. Explain briefly how the rule works in each context