In a mass spectrum, there are two peaks, one at m/z 63.0 with percentage abundance 69.1% and another peak at m/z 65.0 with percentage abundance 30.9%. Determine the relative atomic mass (Ar) for this element, giving the answer to 3 significant figures (no units required).

Explanation:

hope the picture above help u understand:)

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.