Answer:
C (Lake Depth Answer)
Explanation:
Here we want to find the math that ends up with 0.
The stock starts with 12$, but loses 16$.
That's -4$ total, not 0.
The ion starts with 19 protons, and 18 electrons. Protons are postive charges, electrons are negative.
This leaves us with 1 proton, not 0.
The lake depth increases by 6 inches, but evaporates 6.
This leaves us back where we started, with 0.
Ahmed spends 25$, but earns 30$.
This leaves us with $5, not 0.