A stone of mass 5kg is taken to the Moon. Given that MEarthMMoon=811 and REarthRMoon=41, find the approximate weight of the stone on the Moon.\newline\text{(Take }g\,(\text{Earth}) = 9.8\,\text{m s}^{-2}\text{.)}
(a) 8.2N
(b) 49N
(c) 9.8N
(d) 3.1N