A Charged Particle Is Moving Horizontally Westward with a Velocity $\times$

Multiple Choice

A charged particle is moving horizontally westward with a velocity of 3.5 $\times$ 10⁶ m/s in a region where there is a magnetic field of magnitude 5.6 $\times$ 10^-5 T directed vertically downward.The particle experiences a force of 7.8 $\times$ 10^-16 N northward.What is the charge on the particle?

A) +4.0 $\times$ 10^-18 C
B) -4.0 $\times$ 10^-18 C
C) +4.9 $\times$ 10^-5 C
D) -1.2 $\times$ 10^-14 C
E) +1.4 $\times$ 10^-11 C