By Approximately How Many Magnitudes Is the Star Sirius Fainter

question 41

Multiple Choice

By approximately how many magnitudes is the star Sirius fainter than the full Moon in our sky? (See Figure 10-2,Comins,Discovering the Essential Universe,6th ed.)

• A) 15
• B) 2
• C) 11
• D) 5

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Definitions:

Distal Tubule

A portion of the kidney nephron that functions in the reabsorption of water, sodium, and chloride and in the secretion of potassium and hydrogen ions.

Solute Concentration

The amount of a solute that is dissolved in a solvent, determining the concentration of a solution.

Ovulation

The release of an egg from an ovary, an event that occurs usually once in each menstrual cycle, enabling fertilization if sperm are present.

White Blood Cell Count

A measure of the number of white blood cells in a volume of blood, used as an indicator of immune system health.