Answer:
1210
Explanation:
Because the 121 cm times 10 is 1210

The Balanced equation will be :

The Coefficients are :
_____________________________

Answer:k
Explanation:
Atomic theory would be the theory or explanation of the function of atoms and their relationship with each other.
I believe the answer is <span>can be elements or compounds
In this case, elements in the decomposition reaction is the substance that cannot be separated into simpler substances.
Compounds, technically act as a reactant in the decomposition reaction, but since the reaction breakdown one substance into two or more, sometimes it exists in the product.</span>