Answer
5.5 T.
Work Step by Step
In problem 11, it is stated that the energy of a particle (measured in eV) of charge e, traveling in a circular path (radius r, in meters) at relativistic speeds, may be related to the required magnetic field (in tesla) by the relationship
$$E_{electron\;volts}=Brc$$
Solve for the magnetic field.
$$B=\frac{E_{electron\;volts}}{rc}$$
$$B=\frac{(7.0\times10^{12})}{(4.25\times10^3 m)(3.00\times10^8 m/s)}=5.5T$$
