Switching from white bread to wheat bread would be an example of which of the following?
Fungibility
Elasticity
Non-excludability
Substitution

Prices for products became more affordable as a result of new forms of ,witch got things to market faster and cheaper

On a supply and demand graph, equilibrium is the point where the two curves meet. the supply curve begins. the supply curve ends. the demand curve ends.

What is the rule relating the ratio of marginal utility to prices of two goods at the optimal choice? explain why, if this rule does not hold, the choice cannot be utility-maximizing.