X-Rays of Energy 2

Short Answer

X-rays of energy 2.9 × 10⁴ eV are scattered by a free stationary electron through an angle of 135°.What is the energy of the scattered X-rays,in electron volts? (m_el = 9.11 × 10^-31 kg,
e = - 1.60 × 10^-19 C,h = 6.626 × 10^-34 J ∙ s,c = 3.00 × 10⁸ m/s,1 eV = 1.60 × 10^-19 J)