(a)[1]
State the meaning of a galaxy.
(b)[2]
Determine the distance in kilometres (km).
(c(i))[1]
State one observation that can be used to determine the speed at which a galaxy is moving away.
(c(ii))[1]
State one other observation that is used to find the distance to a distant galaxy.
(c(iii))[1]
State the relationship between galaxy speeds and their distances from the Earth.
(c(iv))[2]
Use this value to work out an estimate for the age of the Universe.