Atom Interaction: Solving T=E^2/4*(M+m)c^2

[matt222]

Homework Statement

The problem is attached

Homework Equations

T=E^2/4*(M+m)c^2
M=61amu,
m=1amu
E=710kev
c=3*10^8m/s
I conver amu to kg

The Attempt at a Solution

direct subtitution but the thing that I got the answer which is 2.21eV which is very small and it confused me have I did something wrong or it is true

 

[matt222]

why no one helped me?