Area of rectangle 8 cm × 5 cm.

**The reasoning** Area of a rectangle = length × width You have: - Length = 8 cm - Width = 5 cm So: Area = 8 cm × 5 cm = **40 cm²** That's it! The principle here is **area formula for rectangles** — you multiply the two dimensions together. Notice the unit becomes cm² (square centimeters) because you're multiplying cm by cm. **Why the wrong options tempt you** - **Option A (13 cm²)**: This is 8 + 5. The trap? You *added* instead of multiplied. Addition gives you the perimeter's half (or just... nothing useful here), not area. - **Option B (26 cm²)**: This is 2(8 + 5) = perimeter, not area. You calculated the distance *around* the rectangle instead of the space *inside* it. - **Option D (80 cm²)**: Probably 8 × 10 or some careless multiplication error. Always double-check your arithmetic. **Quick takeaway** Area means "space inside" — always **multiply** length by width; perimeter means "distance around" — that's when you add and multiply by 2.