Why Do Ecologists Say That Earth Is a Closed System

question 54

Multiple Choice

Why do ecologists say that Earth is a closed system for matter?

• A)because there are no new inputs of matter
• B)because there is no net loss of matter
• C)because matter cycles in and out of organisms in ecosystems
• D)because matter stays in the biosphere
• E)All of the answer choices are correct.

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Definitions:

Units

The measures or quantities of a product, service, or resource, which are accounted for in business transactions.

Activity Variance

The difference between the actual cost incurred for an activity and the expected cost, based on the budgeted or standard amount.

Direct Labor

The wages paid to workers who are directly involved in the production of goods or the provision of services.

Units

Units typically refer to the individual items or quantities of a product or service produced or sold by a business.