The population of a town is increasing by 646 people per year. State whether this growth is linear or exponential. If the population is 1600 today, what will the population be in four years?

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.  

gasoline is a mixture. it contains several different kinds of compounds that can be present in a variety of ratios.