Measurement Precision to 0.1 mm

Steps:

• Convert 0.1 mm to cm: 0.1 mm = 0.01 cm, as 1 mm = 0.1 cm.
• Identify readings by decimal places: 3.3 cm (1 decimal = 0.1 cm or 1 mm), 3.31 cm (2 decimals = 0.01 cm or 0.1 mm), 3.310 cm and 3.312 cm (3 decimals = 0.001 cm or 0.01 mm).
• Match precision: The reading to one tenth of a millimeter (0.1 mm) uses two decimal places in cm.
• Select option with exactly that precision.

Why B is correct:

• 3.31 cm expresses measurement to 0.01 cm, equivalent to 0.1 mm per the unit conversion 1 mm = 0.1 cm.

Why the others are wrong:

• A: 3.3 cm is precise to 0.1 cm (1 mm), coarser than 0.1 mm.
• C: 3.310 cm is precise to 0.001 cm (0.01 mm), finer than needed.
• D: 3.312 cm is precise to 0.001 cm (0.01 mm), finer than needed.

Final answer: B