T<span>his reaction, known as nuclear fusion, converts hydrogen atoms into helium. The by-product of nuclear fusion in the </span>Sun's<span> core is a massive volume of </span>energy<span> that gets released and radiates outward toward the surface of the </span>Sun<span> and then into the solar system beyond it.</span>
Sixty-five million years ago, more than three-fourths of all plant and animal species living on Earth becameextinct<span>. This event is known as the </span>K-T<span> mass </span>extinctionbecause it occurred at the boundary between theCretaceous<span> (K) and Tertiary (T) time periods. The most famous group of animals to perish was the dinosaurs.
Hope this helps :)</span>