Can someone help me ?

Explanation:

The Stock System states that In a chemical formula or equation, some metals need a roman numeral after their symbol. If a metal has multiple oxidation states, it needs a roman numeral.

Use the Periodic Table to see the oxidation states for each metal.

We can see that cobalt, iron, and copper have more than one oxidation state, so they would require a roman numeral.

the answer is yes

it has kinetic energy

reason

an object has kinetic energy when you stop the force carrying it, the object will stay in motion.

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