Which adjective does not necessarily describe a known feature of the early universe? (Be sure to consider the universe as a whole, not just the observable universe.)
A) filled with intense radiation B) hot
C) dense D) small
Question 2
Based on its surface temperature of 6,000 K, most photons that leave the Sun's surface lie in which region of the electromagnetic spectrum?
A) infrared B) visible C) microwave D) X-ray E) ultraviolet