What Useful Purpose Did Variable Stars Serve for Harlow Shapley

question 124

Multiple Choice

What useful purpose did variable stars serve for Harlow Shapley in locating the galactic center?

• A) Variable stars are important spiral arm tracers and thus defined the shape of the Milky Way Galaxy.
• B) The brightness variations of variable stars allowed accurate distances to be measured.
• C) Variable stars emit copious amounts of infrared radiation and are thus visible through interstellar dust that obscures visible light.
• D) Variable stars are concentrated in the galactic center and so defined its direction.

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Definitions:

Predetermined Overhead Rates

Overhead rates calculated before a period starts by dividing estimated overhead costs by an expected allocation base.

Machine-Hours

A measure of production output or activity based on the number of hours machines are operating in the manufacturing process.

Machining

The process of removing material from a workpiece to shape or finish it using machine tools.

Manufacturing Overhead

All indirect costs associated with the production process, excluding direct material and direct labor costs.