A Beryllium-8 Nucleus at Rest Undergoes Double Alpha Decay as Follows

Multiple Choice

A beryllium-8 nucleus at rest undergoes double alpha decay as follows:
$${ } _ { 4 } ^ { 8 } \mathrm { Be } \rightarrow { } _ { 2 } ^ { 4 } \mathrm { He } + { } _ { 2 } ^ { 4 } \mathrm { He }$$
The known atomic masses are:
${ } _ { 2 } ^ { 4 } \mathrm { He } : \quad 4.002603 \mathrm { u }$
${ } _ { 4 } ^ { 8 } \mathrm { Be } : \quad 8.005305 \mathrm { u }$
What is the kinetic energy of each departing alpha particle? $\left( 1 \mathrm { u } = 931.5 \mathrm { MeV } / \mathrm { c } ^ { 2 } \right)$

A) $130 \mathrm { keV }$
B) $92 \mathrm { keV }$
C) $180 \mathrm { keV }$
D) $46 \mathrm { keV }$
E) $65 \mathrm { keV }$