Nuclear fusion and gravitational contraction
<span>constituent of star is hydrogen(including isotope) or helium. nuclear fission is almost impossible. D(deuterium; isotope of hydrogen) and T(tritium; also isotope of hydrogen) reacts and helium is formed. During this reaction, severe energy is generated. Heavier elements are formed and pulls each other. Gathered elements forms core of star. Gravity of the core prevents the gas to run away.</span>
Answer: D.
Explanation: Just took the quiz.
Answer:
the elements towards the bottom left corner
This is correct, I just did the test. Yes, displacement is 45 meters, elapsed time is three seconds, and the direction is toward the goal.
