(a(i))[1]
State the name of the force that holds the Moon in orbit round the Earth.
(a(ii))[1]
State the time for the Moon to make one orbit of the Earth. Include the unit.
(a(iii))[3]
Calculate the time taken for the radio signal to travel from the Moon to the Earth.
(b)[3]
Explain how this conclusion supports the Big Bang Theory of the Universe.