The Spiral Galaxy of Which Earth Is a Part Is

question 222

Multiple Choice

The spiral galaxy of which Earth is a part is roughly 14 billion years old. Which of these statements about the stars that formed when the Milky Way Galaxy was very young (say, during the first billion years) is true?

• A) No stars are still on the main sequence-in this time all stars have finished their lives.
• B) All stars of less than 3/4 of the mass of the Sun are still on the main sequence.
• C) All stars of more than 15 times the mass of the Sun are still on the main sequence.
• D) All stars of 3 times the mass of the Sun are still on the main sequence.

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Definitions:

Retina

a layer of tissue at the back of the eye that senses light and sends images to the brain, enabling vision.

Organ of Corti

A structure located within the cochlea of the inner ear, containing hair cells that act as sensory receptors for sound.

Cochlea

A spiral-shaped, fluid-filled inner ear structure crucial for converting sound vibrations into neural signals for hearing.

Temporal Lobe

A region of the brain located at the sides of the brain, responsible for processing auditory information and encoding memory.