Perimeter of a square or rectangle – Given s = 3 cm (interpreted as square side):\nFind the perimeter when the given dimension is s = 3 cm, where s denotes the side of a square.

Introduction / Context:
For a square, perimeter P = 4 * side. The prompt uses s to denote square side.

Given Data / Assumptions:

• s = 3 cm is the side of a square.

Concept / Approach:
Apply P = 4s directly.

Step-by-Step Solution:

Verification / Alternative check:
Add all sides: 3 + 3 + 3 + 3 = 12 cm.

Why Other Options Are Wrong:
13, 14, 15 are not multiples of 3 for a square perimeter.

Common Pitfalls:
Interpreting s as rectangle side without the other dimension.

Final Answer:
12