Earth, Which Is Mostly Rock and Iron, Has a Density

question 300

Multiple Choice

Earth, which is mostly rock and iron, has a density of 5515 kg/m³. Ganymede, Jupiter's largest satellite, contains much water and water ice and has a density of 1940 kg/m³. Io has a density of 3570 kg/m³. What conclusions have astronomers drawn from this?

• A) Io must be composed of some new material other than rocks, iron, water, or ice.
• B) Io is composed of compressed water and water ice.
• C) Io is mostly rock and iron, but because of its smaller mass it cannot compress the material as much as Earth can.
• D) Since Io is smaller than Earth, it is expected to have a smaller density regardless of composition.

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Definitions:

Unfavorable Effect

A situation or outcome in financial analysis or performance metrics where actual results are worse than planned or expected results.

Variances

Discrepancies between planned financial outcomes and the actual results, used in budgeting and accounting to analyze and control costs.

Quantity Variance

A variance that is computed by taking the difference between the actual quantity of the input used and the amount of the input that should have been used for the actual level of output and multiplying the result by the standard price of the input.

Standard Quantity

This refers to the predefined amount of materials or labor deemed necessary to produce a single unit of a product under normal operations.