A laser emits $9\mathrm{.}51{10}^{17}$ photons per second in a beam of light that has a diameter of $2\mathrm{.}56$ mm and a wavelength of $514\mathrm{.}5$ nm $.$ Determine $($a$)$ the average electric field strength and $($b$)$ the average magnetic field strength for the electromagnetic wave that constitutes the beam.

$($a$)$ Number Units

$($b$)$ Number Units