1. **State the problem:** We need to find the perimeter of a trapezoid with a bottom base of 8 cm, a top base of 5 cm, and two sides each measuring 6 cm. 2. **Formula for perimeter of a trapezoid:** The perimeter $P$ is the sum of all its sides: $$P = a + b + c + d$$ where $a$ and $b$ are the bases, and $c$ and $d$ are the sides. 3. **Substitute the given values:** $$P = 8 + 5 + 6 + 6$$ 4. **Calculate the sum:** $$P = 8 + 5 + 6 + 6 = 25$$ 5. **Conclusion:** The perimeter of the trapezoid is 25 cm. **Answer:** a. 25 cm