$\therefore \mathrm{r}=\frac{\mathrm{mv}}{\mathrm{eB}}=\frac{\sqrt{2 \mathrm{mE}}}{\mathrm{eB}}$
or $\quad \mathrm{r}=\frac{\sqrt{2 \times 9.1 \times 10^{-31} \times 880 \times 1.6 \times 10^{-19}}}{1.6 \times 10^{-19} \times 2.5 \times 10^{-3}} \approx 0.04\, \mathrm{m}=4 \,\mathrm{cm}$
$(a)$ the electric field at the axis of wire is zero
$(b)$ the magnetic field at the axis of wire is zero
$(c)$ the electric field in the vicinity of wire is Zero.
$(d)$ the magnetic field in the vicinity of wire is Zero
