The Light from a Distant Cloud of Gas and Dust

question 283

Multiple Choice

The light from a distant cloud of gas and dust looks distinctly red to the unaided eye. When a spectrum is taken, the red color is found to come from a single, bright spectral line. Thus, the red color in this situation is due to

• A) interstellar reddening.
• B) the Balmer spectrum of hydrogen.
• C) the Doppler effect.
• D) interstellar reddening, the Balmer spectrum of hydrogen, or the Doppler effect.

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Definitions:

Unemployment Rate

The percentage of the working-age population that is unemployed and in the process of looking for a job.

Sacrifice Ratio

An economic term that refers to the amount of production or output that must be forgone in order to reduce inflation by one percentage point.

Disinflates

The process of reducing the rate of inflation; a slowing in the rate at which prices increase, typically as a result of monetary policy actions.

Sacrifice Ratio

The sacrifice ratio is an economic concept that measures the cost of reducing inflation in terms of lost output or unemployment.