The Rest Mass of a Proton Is 1

The rest mass of a proton is 1.0072764666 u and that of a neutron is 1.0086649158 u. The ⁷⁵As nucleus weighs 74.92160 u. Calculate the total binding energy of the nucleus.

A) 1.464 × 10^-7 joule
B) 1.019 × 10^-9 joule
C) 2.090 × 10^-9 joule
D) 6.235 × 10^-12 joule
E) 1.255 × 10^-7 joule