What does the presence of new rock near an oceanic ridge indicate? a. There is always a deep-sea trench underneath.
b. There is evidence of seafloor spreading.
c. They are made from oceanic crust.
d. They have iron oriented in different directions.

Which revelation resulted from the observation of the spectrum of different galaxies? a. there were more galaxies whose spectrum was blueshifted b. there were no galaxies whose spectrum was redshifted c. there were more galaxies whose spectrum was redshifted d. there were no galaxies whose spectrum was blueshifted