Answer:

Explanation:
We will need a balanced chemical equation with masses, moles, and molar masses.
1. Gather all the information in one place:
Mᵣ: 18.02
2Na + H₂O ⟶ 2NaOH + H₂
m/g: 72.0
2. Moles of H₂O

3. Moles of Na
The molar ratio is 2 mol Na/1 mol H₂O.

Answer:
C. Metamorphosis
Explanation:
Metamorphosis is really a biological process by which an animal physically develops after birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation
Answer: D) protons.
The other option that would make the most sense would be electrons, however the mass of an electron is so small that is basically negligible, so it's not included in the atomic mass.