Why does a particular gas cloud in the constellation Orion appear red?
A) The atoms in the cloud have electrons that are primarily red.
B) The cloud must be made up of neon and nothing else.
C) The cloud must be made of some element or elements that give off red emission lines.
D) The solid metal inside the cloud is heated to 1000 Kelvin.
E) The gas in the cloud is emitting all colors, but our telescopes only detect red light.
Ans: C) The cloud must be made of some element or elements that give off red emission lines.
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The tallest spot on Earth is Mt. Everest, which is 8850 m above sea level. If the radius of the Earth to sea level is 6370 km, how much does the magnitude of g change between sea level and the top of Mt. Everest?
A. 0.0030 
B. 0.020
C. 0.035
D. 0.025
E. 0.030
What is a major limitation in the Doppler method for detecting extrasolar planets?
A) it is better at finding massive planets like Jupiter rather than small planets like the Earth B) it is best suited to finding planets which orbit relatively close to their star C) it requires the use of fairly large telescopes and long exposures which limits the number of star that can be studied D) all of these are major limitations
The root-mean-square speed (thermal speed) for a certain gas at 100°C is 0.500 km/s. If the temperature of the gas is now increased to 200°C, the root-mean-square (thermal) speed will be closest to
A) 563 m/s. B) 634 m/s. C) 707 m/s. D) 804 m/s. E) 1000 m/s.
The two headlights of a car are wired:
1.in series with each other. 2.in parallel. 3.neither in series or in parallel. 4.It is impossible to tell.