You Have Taken a Picture of a Galaxy 1 Billion

question 5

Multiple Choice

You have taken a picture of a galaxy 1 billion light years away. That picture shows:

• A) a galaxy that is 1 billion years old.
• B) a galaxy that is 13 billion years old.
• C) a galaxy as it was 1 billion years ago.
• D) a galaxy that is 1 billion light years old.

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Definitions:

Termination Reaction

A chemical reaction that halts the growth of a polymer chain by removing reactive intermediates, ending the polymerization process.

Photochemically Initiated

Describes a process or reaction that begins when light energy is absorbed by a chemical substance.

Methane

A colorless, odorless, flammable gas that is the simplest alkane, consisting of one carbon atom bonded to four hydrogen atoms.

Chlorine

A chemical element with the symbol Cl and atomic number 17, known for its extensive use in disinfection and its role as a bleaching agent.