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Title: Which of the following statements is true of reflection nebulae? Post by: tifoanug on Mar 19, 2018 Which of the following statements is true of reflection nebulae?
A) They have a distinctive blue color. B) The gases in reflection nebulae are excited to emit photons. C) The spectrum of a reflection nebula is not the reflected absorption spectrum of starlight. D) They are produced when a hot star excites the gas to produce an emission spectrum. Question 2 _____ is a series of three nuclear reactions that builds a helium nucleus by adding protons one at a time. A) The proton-neutron chain B) The helium proton chain C) The proton-proton chain D) The hydrogen-helium chain Question 3 _____ are reactions that join the nuclei of atoms to form more massive nuclei. A) Endothermic reactions B) Nuclear fission reactions C) Nuclear fusion reactions D) Chemical reactions Question 4 The carbon-nitrogen-oxygen (CNO) cycle works best in temperatures: A) lower than 10,000,000 K. B) higher than 16,000,000 K. C) higher than 11,000,000 K but lower than 12,000,000 K D) higher than 13,000,000 K but lower than 15,000,000 K Question 5 When the nuclear reactions begin making too little energy in a star, by virtue of the natural thermostat, the star: A) would expand slightly. B) would reduce its central temperature. C) would increase its density. D) would increase the mass by a factor of 2. Title: Which of the following statements is true of reflection nebulae? Post by: sammholder on Mar 19, 2018 Content hidden
Title: Which of the following statements is true of reflection nebulae? Post by: tifoanug on Mar 19, 2018 Amazing, correctly answered
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