An Electron Enters a Magnetic Field of with a Velocity

An electron enters a magnetic field of with a velocity perpendicular to the direction of the field. At what frequency does the electron traverse a circular path? (m_el = 9.11 × 10^-31 kg, e = 1.60 × 10^-19 C)

A) 2.1 × 10¹⁰ Hz
B) 4.8 × 10^-7 Hz
C) 2.1 × 10¹⁴ Hz
D) 4.8 × 10^-11 Hz