It is possible that the universe may
a. further break itself apart, creating new structures in space.
b. explode within the next million years.
c. continue to expand forever.
d. dissipate from lack of sufficient matter.

Acertain sound is recorded by a microphone. the same microphone then detects a second sound, which is identical to the first one except that the amplitude of the pressure fluctuations is larger. in addition to the larger amplitude, what distinguishes the second sound from the first one? it is perceived as higher in pitch. it is perceived as louder. it has a higher frequency. it has a longer wavelength.