Who are dissidents? What role did they play in the Tiananmen protests of 1989?

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

The process by which liquid water changes into water vapour is called what ?

Which statement about this figure is false