What Is the Lifetime on the Main Sequence of a 2-Solar-Mass

question 2

Multiple Choice

What is the lifetime on the main sequence of a 2-solar-mass star compared to the approximately 10-billion-year life of our Sun? Pick the best answer.

• A) 1.8 × 10¹¹ years
• B) 1.8 × 10¹⁰ years
• C) 1.8 × 10⁸ years
• D) 1.8 × 10⁶ years
• E) 1.8 × 10³ years

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Definitions:

Neurotropic Factors

Proteins that are essential for the development, function, and survival of nerve cells, or neurons.

Brain Cells

Cells found in the brain which include neurons and glial cells, responsible for processing and transmitting information.

Neuroblasts

Immature neuronal cells capable of dividing and differentiating into various types of neurons.

Glioblasts

Immature glial cells that can differentiate into various types of glial cells in the central nervous system.