A gamma ray with 700KeV energy is Compton-Scattered from an electron. Find the energy of the photon scattered at 110 degrees, the energy of the scattered electron, and the recoil angle of the electron

mp=mass of proton=1.673x10^-27
λ=h/mpc(1-cosθ)
λ=(6.6261x10^-34/(1.673x10^-27*3x10^8))(1-cos110)
λ=1.771^-15m
f=c/λ
f=3x10^8/1.771x10^-15
f=1.693x10^23 Hz
h=4.1357x10^-15eV/Hz
E=hf
E=(4.1357x10^-15*1.693x10^23)
E=7.0x10^8eV