Answer
The ratio of the energy released in the star-antistar collision to the energy released in the supernova is $~~2400$
Work Step by Step
The mass of the sun is $2.0\times 10^{30}~kg$
We can find the energy released in the star-antistar collision:
$E = mc^2$
$E = (2)(2.0\times 10^{30}~kg)(3.0\times 10^8~m/s)^2$
$E =3.6\times 10^{47}~J$
We can find the ratio:
$\frac{3.6\times 10^{47}~J}{1.5\times 10^{44}~J} = 2400$
The ratio of the energy released in the star-antistar collision to the energy released in the supernova is $~~2400$
