Sally's teacher tells her to find the masses of a sugar cube and a glass of water. sally finds the masses to be 10 g for the sugar cube and 100 g for the glass of water. then, the teacher tells her to put the sugar cube into the water. sally puts the cube into the glass of water and watches as it dissolves. then, the teacher tells sally to estimate the new mass of the glass of sugar-water.
what should sally guess as the new mass of the glass of sugar-water?

Sally should guess that the glass of sugar-water will have a mass of 110 g since the masses from the glass of water (100 g) and the sugar cube (10 g) will combine. it will be 110

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.