To maximize the social pie, a tax on pollution must equal the external cost created by the polluting activity

The implication of Say's law is that

A) a barter economy is the most efficient economy. B) increased consumption today leads to increased production tomorrow. C) overproduction in a market economy is not possible. D) Gross Domestic Product is the same whether we use the expenditure approach or the income approach.

To calculate gross domestic product, you use the sum of the market values of all final goods and services produced in a given year. This means you

A) count the total number of final goods and services produced in the marketplace in that particular year and then add the numbers together. B) count the total number of final goods and services produced in the marketplace from every year including that given year and then add the numbers together. C) value the final goods and services at their market prices for that particular year, multiply them by the quantity produced that year, and then add the numbers together. D) value the final goods and services at their market prices for that particular year, multiply them by the quantity produced from every year including that given year, and then add the numbers together.