The correct answer is D. Elements are created that differ from the reactants.. Because in a eeaction, the product is different than the reactants. Take NaCl for example.
Endocrine system im pretty sure
Answer:
Attraction, and repulsion!
Explanation:
Magnets have a north pole ans south pole, so when you put south pole and south pole toghther it creates repulsion, and when you put the north pole and north pole it still creats repulsion, but when a south pole and a north pole are put together it creats attraction, your welcome!
An open system is
when there is a transfer of energy and matter with its surroundings.
A closed system is
where there is a transfer of energy, may it be heat or work, but not matter
with its surroundings.
An isolated system
is where there is no transfer of energy or matter with its surroundings.