A charged particle of mass = 6.2 g and charge q is moving with a velocity v = 18.0 m/s and enters a region of space that has a uniform magnetic field B_in that is directed at 90with particle's initial velocity. The magnetic force of magnitude 0.39 N acts on the particle and causes it to move in a semicircular path as shown in the figure below. Determine the radius r of the semicircular path. Give answer in meters and to two places to the right of the decimal.

BIXXXXX Bin X x X X X X V XXXX IA X XXXX