Charge of electron/proton = 1.6*10^-19 coulombs
Mass of proton m1 = 1.67*10^-27 kg
Mass of electron m2 = 9.109 × 10-31 kg
Given :- Speed v = 2.64*10^7 m/s
Radius R = 160 m
R = m*v / (q*B)
q*B = m*v / R
B = m*v / (R*q)
For proton
B = 1.67*10^-27 * 2.64*10^7 / (160 * 1.6*10^-19)
B = 1.722 *10^-3
Now for electron
B = 9.109*10^-31 * 2.64*10^7 / (160 * 1.6*10^-19)
B = 9.39 *10^-7