Which is true about cold dark matter?
a) Cold dark matter interacts strongly with ordinary baryonic matter via the strong force.
b) Cold dark matter particles travel faster than the speed of light.
c) Cold dark matter particles travel more slowly than hot dark matter particles.
d) Cold dark matter exists only within planets and stars but not in other parts of galaxiesor intergalactic space.
e) Cold dark matter emits X-rays, but no other forms of radiation.
Ans: c) Cold dark matter particles travel more slowly than hot dark matter particles.
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Based on current evidence concerning the amount of deuterium in the universe, we can conclude that
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For a system undergoing an isothermal process,
a. 
b. 
c. 
d. 
e. 