Four particles of masses 1kg, 2kg, 3kg and 4kg respectively are located at the corners of a square of 1 m side. If 1 kg is taken at the origin, 2kg and 3 kg are on x and y axes then the coordinates of centre of mass are
A.(0.4m,0.5m)
B.(0.5m,0.7m)
C.(0.5m,0.6m)
D.(0.6m,0.7m)