Final answer:
When r = 3 cm, the exact value is 3 cm. The approximation to the nearest hundredth is 3.06 cm.
Step-by-step explanation:
When r = 3 cm, the exact value is 3 cm. To approximate to the nearest hundredth, we look at the tenths digit. Since the tick marks go up to 3.0 cm and the next decimal place is estimated to be about six-tenths of the way between the third and fourth tick marks, we estimate the hundredths place as 6.
Therefore, the approximation to the nearest hundredth is 3.06 cm.