Answer
$\lambda = 223~nm$
Work Step by Step
We can find the wavelength of the light:
$K_{max} = \frac{h~c}{\lambda} - E_0$
$K_{max}+E_0 = \frac{h~c}{\lambda}$
$\lambda = \frac{h~c}{K_{max}+E_0}$
$\lambda = \frac{(6.626\times 10^{-34}~J~s)(3.0\times 10^8~m/s)}{(1.30~eV+4.28~eV)(1.6\times 10^{-19}~J/eV)}$
$\lambda = 2.23\times 10^{-7}~m$
$\lambda = 223~nm$
