Here's how to determine the number of atoms in the molecule C₁₄H₁₂O₃:

* Count the subscripts:

* Carbon (C): 14 atoms

* Hydrogen (H): 12 atoms

* Oxygen (O): 3 atoms

* Total atoms: 14 + 12 + 3 = 29 atoms

Therefore, there are 29 atoms in a single molecule of C₁₄H₁₂O₃.