Answer:

Explanation:
The fusion reaction in this problem is

The total energy released in the fusion reaction is given by

where
is the speed of light
is the mass defect, which is the mass difference between the mass of the reactants and the mass of the products
For this fusion reaction we have:
is the mass of one nucleus of hydrogen
is the mass of one nucleus of helium
So the mass defect is:

The conversion factor between atomic mass units and kilograms is

So the mass defect is

And so, the energy released is:

Answer: Main sequence stars fuse hydrogen atoms to form helium atoms in their cores. About 90 percent of the stars in the universe, including the sun, are main sequence stars. These stars can range from about a tenth of the mass of the sun to up to 200 times as massive.