$$\text { If } x \text { varies inversely as } y ^ { 2 } \text {, and } x = 2 \text { when } y = 20 \text {, find } x \text { when } y = 5 \text {. }$$

question 49

Multiple Choice

$$\text { If } x \text { varies inversely as } y ^ { 2 } \text {, and } x = 2 \text { when } y = 20 \text {, find } x \text { when } y = 5 \text {. }$$

• A) 50
• B) 32
• C) 16
• D) 4

Differentiate between open and closed circulatory systems including examples of organisms with each system.

Identify and compare the structure and function of various types of blood vessels.

Describe the heart's anatomy, including the location and function of its valves.

Understand the risk factors for cardiovascular disease, including modifiable aspects.

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Definitions:

Independent Variable

The variable in an experiment that is manipulated to observe its effect on the dependent variable.

Dependent Variable

The variable in an experiment that is affected by manipulation of the independent variable, and is measured or observed by the researcher.

Control Variable

An experimental element which is constant and unchanged throughout the course of the investigation to ensure that the effect of the independent variable can be measured accurately.

Control Group

In experimental research, a group of subjects that is not exposed to the experimental treatment, serving as a comparison point.