For a current-carrying wire running perpendicular to a magnetic field, the magnetic force acting on the wire is given by:
F = ILB
F = magnetic force, I = current, L = wire length, B = magnetic field strength
Given values:
F = 0.60N, L = 1.0m, B = 0.20T
Plug in and solve for I:
0.60 = I(1.0)(0.20)
I = 3.0A