Answer
$ m=939\frac{MeV}{c^2}$
Work Step by Step
The mass is found by using equation 26–7.
$$E=mc^2$$
$$m=\frac{E}{c^2}=\frac{1}{c^2}mc^2$$
$$m=\frac{1}{c^2}\frac{(1.67\times10^{-27}kg) (3.00\times10^8m/s)^2}{1.60\times10^{-13}J/MeV}$$
$$m=939\frac{MeV}{c^2}$$
(If we had used more significant figures for the calculation, the answer would have been $938\frac{MeV}{c^2}$.)