We Detect Neutral Gas in the Interstellar Medium by Looking

question 80

Multiple Choice

We detect neutral gas in the interstellar medium by looking for radiation at 21 cm that arises when:

• A) an electron moves from the n = 1 to n = 2 state in a hydrogen atom
• B) an electron is ionized from a hydrogen atom
• C) carbon monoxide (CO)gas is excited by stellar radiation
• D) the spin of an electron flips and aligns with the spin of a proton in a hydrogen atom

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Mark-Up Percentage

The percentage added to the cost price of goods to cover overhead and profit, determining the selling price.

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A fee or cost applied for the materials used in the manufacturing or production of goods.

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Price Skimming

A pricing strategy where a company charges the highest initial price that customers will pay and then lowers it over time.