"The terminal speed of a sphere of gold
(density = 19.5 kg m–3) is 0.2 m s–1 in a viscous
liquid (density = 1.5 kg m–3). Then the terminal
speed of a sphere of silver (density = 10.5 kg m–3)
of the same size in the same liquid is
(a) 0.1 m s–1 (b) 0.4 m s–1
(c) 0.2 m s–1 (d) 0.3 m s–1"