The potential difference for a distance of \\\\(20 m\\\\) is \\\\(2 \\ joule/kg\\\\).Now work done \\\\(=m \ imes\\\\) potential difference.Thus work done for a distance of \\\\(4 m\\\\) for a mass \\\\(5 kg\\\\), \\\\(W= \\dfrac{4}{20} \ imes 2 \ imes 5\\\\)\\\\(\\implies W= 2 J\\\\)