Galaxy Clusters Have Been Observed to Be Rich in Hot,X-Ray-Emitting

question 27

Multiple Choice

Galaxy clusters have been observed to be rich in hot,X-ray-emitting gas.What is keeping the gas in the cluster?

• A) dark matter
• B) the gravitational pull of the galaxies
• C) the electromagnetic radiation emitted by the galaxies
• D) the low speed of the hot gas

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Definitions:

Cash Expenses

Outlays of cash during a given period for direct charges such as wages, rent, and utilities.

Net Present Value (NPV)

The gap between the current value of cash entering and the current value of cash exiting over a timeframe, employed in investment planning to evaluate the profitability of projects.

Capital Cost Allowance (CCA)

Depreciation for tax purposes, not necessarily the same as depreciation under International Financial Reporting Standards; depreciation method under Canadian tax law allowing for the accelerated write-off of property under various classifications.