Variable Stars Such as Cepheid Variables Are Used in What

question 360

Multiple Choice

Variable stars such as Cepheid variables are used in what important measurement in astronomy?

• A) the measurement of the distances to stars
• B) the measurement of the rotation speeds of galaxies
• C) the measurement of the surface temperatures of stars
• D) the keeping of accurate time

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Definitions:

Collision Theory

A theory that proposes chemical reactions occur and proceed at a certain rate based on the concentration, velocity, and orientation of reacting particles during collisions.

Rate Of Formation

The speed at which a product is created in a chemical reaction, usually measured in moles per liter per second.

High-energy Particles

Particles that possess energy significantly greater than average, often referring to subatomic particles such as protons, neutrons, and cosmic rays.

Accumulated Degree Hours

A measurement unit for the thermal energy accumulated, used in forensic entomology to estimate the time since death based on insect development.