Grasses and mosses sprout in alaska’s tundra in summer when

a. the soil is fertile

b. rainfall is adequate

c. the top layer of soil freezes

b. the top layer of soil thaws

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