Question

according to big bang theory, the universe started out with a very hot beginning, and has been cooling and expanding ever since. which two observations of cosmic microwave background radiation support big bang theory? a. cosmic microwave background radiation redshifted and increased in mass over time. b. cosmic microwave background radiation exists in all areas of the observable universe. c. cosmic microwave background radiation contains all of the dark matter necessary to start the big bang. d. cosmic microwave background radiation stores the same amount of energy the big bang likely released. e. cosmic microwave background radiation has a relatively consistent temperature throughout the observable universe.

Explanation:

• Option B: The cosmic microwave background (CMB) radiation is isotropic (exists uniformly in all areas of the observable universe), which is consistent with the Big Bang theory's prediction of a homogeneous early universe.
• Option E: The CMB has a relatively consistent temperature (about 2.725 K) throughout the observable universe, with tiny fluctuations. This uniformity supports the idea of a hot, dense initial state that expanded and cooled uniformly, as proposed by the Big Bang theory.
• Option A is incorrect as CMB does not increase in mass over time, and redshift of CMB is related to cosmic expansion but not mass increase. Option C is incorrect as CMB is not related to dark matter for starting the Big Bang. Option D is incorrect as the energy stored in CMB is not the same as the energy released by the Big Bang in a simple "stored" sense; the CMB is the afterglow of the Big Bang's early radiation.

Answer:

B. Cosmic microwave background radiation exists in all areas of the observable universe.
E. Cosmic microwave background radiation has a relatively consistent temperature throughout the observable universe.