Answer: N-14
Explanation: When C-14 undergoes radioactive decay, atoms of N-14 are formed
<span>Enzymes
These are characterized by macromolecular natural impetuous with catalysts that quicken synthetic responses. The particles where upon proteins may act are called substrates and the chemical changes over the substrates into various atoms which are their by products</span>
The correct answer would be the third option. The correct plan for the experiment would be that the type of salt and the amount of water are controls, and the amount of salt and the density are variables. Sheila wants to know the affect of varying the amount of salt to the density so it is the density and the amount of salt that is being changed while the type of salt and the water are kept constant since they are not being investigated.