If a gas initially has a pressure of 8 atm, a volume of 2 liters, and a temperature of 200 K, and then the pressure rises to 14 atm and temperature increases to 300 K, what is the new volume of the gas?

it is the most commonly accepted one

answer is: nuclear fusion produces elements that are heavier than helium.

nuclei combine to form a heavier nucleus, releasing energy.  

for example, fusion of hydrogen atoms at the sun.  

this fusion nuclear reaction is in the inner core of the sun and hydrogen (atomic number 1) is conveted into helium (atomic number 2).  

the inner core is the central region of the sun and all solar energy is produced in the core by nuclear fusion.