1. **State the problem:** We are given a circle with radius $r = 6.8$ cm. 2. **Find the diameter:** The diameter $d$ of a circle is twice the radius. The formula is: $$d = 2r$$ Substitute $r = 6.8$: $$d = 2 \times 6.8 = 13.6$$ So, the diameter is 13.6 cm. 3. **Find the circumference:** The circumference $C$ of a circle is given by: $$C = 2\pi r$$ Using $r = 6.8$ and $\pi \approx 3.1416$: $$C = 2 \times 3.1416 \times 6.8 = 42.7$$ Rounded to 1 decimal place, the circumference is 42.7 cm. **Final answers:** - Diameter = 13.6 cm - Circumference = 42.7 cm