To make 300 ml of oxygen at 20 degrees change it’s volume to 250 ml, what must be done to the sample if it’s pressure and mass are to be held constant ?

i think its 100.

hope this !

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.