Use the Following Figure to Answer the Question

question 31

Multiple Choice

Use the following figure to answer the question.

After looking at the results in the figure, what can be concluded about productivity in the experimental ecosystem?

• A) Productivity is higher at depth than at the surface, but only initially.
• B) Productivity is higher at the surface than at depth; however, an additional experiment could further test the effect of depth by introducing FeSO₄ at 30 m deep and measuring the chlorophyll a response.
• C) Productivity is higher at the surface than at depth, and would be predicted to increase sharply after day 12.
• D) Productivity at a depth of 30 m is low only because of a lack of sunlight, not a lack of iron sulfate.

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Definitions:

Consumer Surplus

The difference in total spending willingness among consumers for a good or service versus their real outlay.

Binding Price Floor

A government-imposed price control or limit on how low a price can be charged that is above the equilibrium price, leading to surplus.

Consumer Surplus

The discrepancy in the total sum consumers are willing to offer for a good or service compared to what they actually offer.

Producer Surplus

The difference between the amount producers are willing and able to supply a good for and the amount they actually receive.