Question

a star is twice as massive as the sun.will its lifespan be longer, shorter, or the same as that of the sun

Answer 1

It will most likely have a shorter life span because its too big to be stable. Hope this helps :)

Answer 2

If a star is large, that means it will burn fuel faster because of its large volume.  the more fuel burned, the hotter it gets. this means the life span will end much sooner before the sun, and it is about to enter the last stage of its life-the red giant.