A particle moving in the xy-plane is subject to a force (x + y) (x2 + y2)3/2' where x and y are in meters. Calculate the work (in J) done on the particle by this force as it moves in a straight line from the point (4 m, 6 m) to the point (7 m, 8 m). F(x, y) = (60 N. m).