Mercury Is Always Much Closer to the Sun Than Venus

question 41

Multiple Choice

Mercury is always much closer to the Sun than Venus is, and yet it never appears brighter than Venus, even at maximum brightness. Explain.

• A) We never see more than a small fraction of Mercury's illuminated surface because of its orbital path relative to that of Earth; hence it always appears dark.
• B) Mercury has a thick atmosphere that impedes reflection from its surface and hence appears dark.
• C) Mercury has a high albedo, or reflectivity, but it is very small and hence appears relatively dark.
• D) Mercury is small, has a dark surface, and has no reflecting clouds.

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Definitions:

Correlational Studies

Studies in which the investigator analyzes the relationships among variables that were in place before the study, without manipulating those variables.

Placebo Effects

Observable or measurable changes in health or behavior resulting from the administration of a placebo, demonstrating the power of belief and expectation in the healing process.

Double-blind

A study design in which neither the participants nor the experimenters know who is receiving a particular treatment, to prevent bias in the results.

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A mental health disorder characterized by a persistent pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development.