Spiral arms appear bright because ________
A) they contain far more stars than other parts of the galactic disk
B) they are the only places where we find stars within the disk of the galaxy
C) they contain more molecular clouds than other parts of the disk
D) they contain more hot young stars than other parts of the disk
D
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Describe evidence of crustal movement (horizontal or vertical) on Venus. Select all that apply.
a. Large composite volcanoes. b. Widespread folded mountain ranges. c. Fault and deep chasms. d. Rare folded mountain ranges. e. Coronae.
A plastic block of dimensions 2.0 cm × 3.0 cm × 4.0 cm has a mass of 30. grams. What is its density?
A) 1.2 g/cm3 B) 1.6 g/cm3 C) 1.3 g/cm3 D) 0.80 g/cm3 E) 2.3 g/cm3
The index of refraction of a type of glass is 1.50, and the index of refraction of water is 1.33. If light enters water from this glass, the angle of refraction will be
A) greater than the angle of incidence. B) equal to the angle of incidence. C) less than the angle of incidence.
What is a planetary nebula?
What will be an ideal response?