Trees Are Among the Largest and Oldest Living Things on Earth

question 18

Multiple Choice

Trees are among the largest and oldest living things on Earth. Like all life on Earth, the majority of a treeʹs biomass is carbon based. What is the source of this carbon?

• A) Fertilizers
• B) Crushed rock and water
• C) Air
• D) Water
• E) The organic layer of the soil

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Definitions:

Income Share

The proportion of total income earned by a specific group, often used in discussions of income inequality.

Normal Profit

The minimum level of profit necessary for a company to remain competitive in the market, essentially covering opportunity costs.

Economic Profit

Profits calculated after considering both explicit costs, like materials and labor, and implicit costs, like opportunity costs, differentiating it from accounting profits.

Pure Rate of Interest

The theoretical return on an investment with no risk of financial loss, representing the time value of money.