Answer:
They are both pretty soft for metals, but magnesium is significantly harder than calcium using this scale . Mg = 2.5, Ca = 1.75. The larger the number, the harder
Explanation:
Jovian planets are what we call the "gas giants," so immediately we can eliminate craters or volcanos because they don't have a solid surface. asteroids in space doesn't belong to any specific planet, so the answer is ring systems.
you can google it and it pops up right away
your answer is b hope this helps