(a)[4]
Show that the distance for $1$ light-year is $9.5 \times 10^{15}\,\text{m}$.
(b(i))[1]
State one measurement made when finding the speed $v$ at which a galaxy is receding from the Earth.
(b(ii))[1]
Write down an equation connecting $v$ with the distance $d$ of a distant galaxy.
(b(iii))[1]
State how the distance $d$ of a distant galaxy may be found by another method, rather than by using the equation in (ii).