Which Technique Has Been Successful in Identifying Good Candidates for a Black

question 26

Multiple Choice

Which technique has been successful in identifying good candidates for a black hole in the Milky Way Galaxy?

• A) detection of extremely redshifted starlight from a region in the nearby spiral arm of the Galaxy
• B) detection of X-rays from a binary star undergoing mass exchange, where masses of component stars can be determined
• C) detection of an extremely dark point in the sky from which no light at all is seen
• D) gravitational lensing of light from a distant object by the black hole to produce two identical images

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Definitions:

Cash Payback Period

The duration of time it takes for an investment to generate enough cash flow to recover its initial cost.

Net Income

The total earnings of a company after all expenses and taxes have been deducted from revenues, indicating profitability.

Straight-Line Rate

A method of calculating depreciation by dividing the difference between an asset's cost and its salvage value by the number of years it is expected to be used.

Annual Rate

The interest rate or growth rate over a period of one year, used for comparing investment returns or loan costs.