Answer: a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.
Explanation: definition
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>
Von Steuben turned the ragged Continental Army into a more effective fighting force by drilling and teaching the army discipline