Please Use the Following Information to Answer the Question(s) Below

question 37

Multiple Choice

Please use the following information to answer the question(s) below.
A scientist conducts an experiment to quantify the effect of mycorrhizae and soil nitrogen levels on plant growth in a grassland. The experiment has four treatments: (1) Mycorrhizae present and ambient levels of nitrogen, (2) mycorrhizae present and nitrogen added, (3) mycorrhizae absent and ambient levels of nitrogen, and (3) mycorrhizae absent and nitrogen added. After four weeks, the scientist removes the aboveground plant material for weighing. Figure 42.4.
-What is the dependent variable in the experiment shown in Figure 42.4?

• A) net primary productivity
• B) gross primary productivity
• C) net secondary productivity
• D) standing crop

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Definitions:

Objective Test

A form of assessment that measures an individual's knowledge or ability in a specific area through questions with preset correct answers, minimizing subjective judgment.

Empirical

Based on, concerned with, or verifiable by observation or experience rather than theory or pure logic.

Known Groups

Refer to specific, identified groups used in research studies to validate the measures or outcomes.

Binomial Effect Size Display

A statistical method to present the effect size of research findings in a more interpretable way by showing how a treatment influences outcomes in a hypothetical scenario of 100 cases.