i belive it is d. both a and c
mark me branliest, only got it 1
the answer is c) isotopes
(i think im spelling it wrong)
an olliptical orbit is a non circular orbit around somethin
this is an example of newton's first law of motion:
an object at rest will remain at rest unless an unbalanced force acts upon it. similarly, a moving object will remain moving in a straight line at constant velocity unless an unbalanced force acts upon it.
the answer is c.