Two straight conductors P and Q are placed separately in the same uniform magnetic field of 0.5 T. Each conductor is perpendicular to the field but only part of Q lies inside the field region. For P, the length in the field is 0.10 m and the current is 4 A. For Q, the length in the field is 0.08 m and the current is 6 A. The ratio of magnetic forces FP:FQ is
a) 2 : 3
b) 5 : 4
c) 5 : 6
d) 6 : 5