If We Say That a Galaxy Has a Lookback Time

question 60

Multiple Choice

If we say that a galaxy has a lookback time of 1 billion years,we mean that

• A)its light traveled through space for 1 billion years to reach us.
• B)is now 1 billion light-years away.
• C)it was 1 billion light-years away when the light left the galaxy.
• D)it is 400 million years old.

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Definitions:

Revenue Account

An account that tracks the income earned by a business, from sales or other sources, during an accounting period.

Expense Account

An account used to record the consumption of assets, including costs incurred in the operation of a business, contributing to a reduction in equity.

Merchandise Inventory

Goods a company intends to sell to customers, typically in a retail or wholesale setting.

Replacement Price

The current cost of replacing an asset or inventory with a similar item.