Global warming is caused by an increase in the amount of ___​

How many time zone are there on earth

Look at the photo i can’t do geography

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