Final answer:
To estimate the circumference of a circle, you can use the formula C = 2πr, where C is the circumference and r is the radius.
Step-by-step explanation:
To estimate the circumference of a circle, you can use the formula C = 2πr, where C is the circumference and r is the radius. In this case, the circumference is approximately 42 cm, so we can estimate the radius as 42 cm / (2π) = 6.68 cm (rounded to two decimal places).
To estimate the diameter, we can double the radius: 6.68 cm × 2 = 13.36 cm (rounded to two decimal places).
Therefore, we can estimate that the circumference of the circle is approximately 42 cm and the diameter is approximately 13.36 cm.