1. Efficiency is the most possible productivity gained from an operation, good, or service with the least amount of time, energy, or money used in transaction costs.
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1. Efficiency is the most possible productivity gained from an operation, good, or service with the least amount of time, energy, or money used in transaction costs. An example sentence: It is much more efficient to do the dishes quickly when your mom asks you to, than complaining and whining. That will simply waste even more time than just doing the dishes and getting it over with.
2. A & B must be substitutes while X & Y are complements.
2. A & B must be substitutes while X & Y are complements.