Answer
$E = 0.256~MeV$
Work Step by Step
The wavelength of the scattered gamma rays is $~~4.86\times 10^{-12}~m$
We can find the photon energy of the scattered rays:
$E = \frac{hc}{\lambda}$
$E = \frac{(6.63\times 10^{-34}~J~s)(3.0\times 10^8~m/s)}{4.86\times 10^{-12}~m}$
$E = 4.0926\times 10^{-14}~J$
$E = (4.0926\times 10^{-14}~J)(\frac{1~eV}{1.6\times 10^{-19}~J})$
$E = 2.56\times 10^5~eV$
$E = 0.256~MeV$
