At Least 70% of Stars Have Planets

question 24

Multiple Choice

At least 70% of stars have planets. How many planets can astronomers reasonably claim exist in the Milky Way galaxy?

• A)at least 1 trillion
• B)at least 70 billion
• C)at least 3000
• D)at least 8

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Definitions:

Melatonin

A hormone, secreted by the pineal gland, that is involved in the regulation of daily biological rhythms.

Oxytocin

A hormone and neurotransmitter involved in childbirth and lactation, also known as the "love hormone," it plays a role in social bonding, sexual reproduction, and during and after childbirth.

Prefrontal Cortex

The part of the frontal lobes of the brain that is involved in decision making, problem-solving, control of purposeful behaviors, consciousness, and emotions.

Right Hemisphere

The half of the brain that is typically associated with spatial abilities, face recognition, visual imagery, and music perception.