We can see each other in the classroom right now because we
A) emit thermal radiation.
B) emit visible light.
C) emit infrared light.
D) reflect visible light.
E) reflect infrared light.
Question 2
Of the normal elements around us, the Big Bang produced
A) none, only energy.
B) only hydrogen.
C) hydrogen and helium.
D) all elements up to iron.
E) all elements in much their present proportions.