which one is greater 15g or 5oz

15g is the correct answer

I think your 'g' stands for 'gram', and I'll work the problem that way.

On Earth, 1 ounce is the weight of about 28 grams of mass.

So around here, 5 ounces is much heavier than 15 grams of mass.

BUT ... On the Sun, where the acceleration of gravity is about 28 times

as much as on Earth, the same 15 grams of mass would weigh about

14.8 ounces.