About 75% of the Mass of the Visible Universe Is

question 97

Multiple Choice

About 75% of the mass of the visible universe is composed of which element?

• A) Helium
• B) Iron
• C) Hydrogen
• D) Silicon

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Definitions:

Korsakoff's Disease

A chronic memory disorder caused by severe deficiency of thiamine (vitamin B1), most commonly caused by alcohol addiction.

Alzheimer's Disease

A progressive neurodegenerative disorder that causes memory loss, cognitive decline, and ultimately, loss of ability to perform daily activities.

Reconstructive Memory

The theory that memories are not exact recordings but rather reconstructions that may be influenced by other cognitive processes, leading to alterations over time.

Difficulties

Challenges or obstacles that make a task hard to accomplish.