Question

about 3 cm
shorter than 9 cm
between 9 and 18 cm
longer than 18 cm

Explanation:

Step1: Estimate number of units

Count the number of segments of about 3 - cm length. There are 6 such segments.

Step2: Calculate length

Multiply the number of segments by the length of each segment. $6\times3 = 18$ cm. Since the object seems to be a bit shorter than a perfect 6 - segment length, it is shorter than 18 cm and clearly longer than 9 cm.

Answer:

Between 9 and 18 cm