Hey im doing a chemistry lab and im confused on if im doing this correctly. Im calculating the volume and i'm not sure it's suppose to be one... please help :(

i know D=m/v but it doesn't seem right nor is there any sig figs

Afusion reaction takes place between carbon and another element. neutrons are released, and a different element is formed. the different element is a) lighter than helium.b)heavier than helium.c)the same weight as helium.d)dependent on the element that reacted with carbon.