Why Is Cecilia Payne's Ph

question 93

Multiple Choice

Why is Cecilia Payne's Ph.D.thesis sometimes called "the most important in astronomy"?

• A)She was the first person to show that the Sun is mostly hydrogen.
• B)She was the first person to analyze spectra of stars.
• C)Her analysis of stellar spectra showed that stars generate their own light.
• D)Her analysis of the Sun's spectrum resulted in the discovery of helium.

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Definitions:

Elasticity of Demand

A measure of how much the quantity demanded of a good responds to a change in the price of that good.

Total Revenue

The total income generated by a firm from the sale of its products or services before any costs are deducted.

Perfectly Inelastic Demand

A market situation where the quantity demanded does not change irrespective of changes in price.

Downward-Sloping

A graphical representation indicating a decrease or decline in value, often used in economics to describe demand curves.