Final answer:
The more precise measurement between 6 mL and 0.6 mL is 6 mL because it indicates accuracy to the nearest mL. For 180 cm and 21 mL, they are units for different measurements, length vs volume, and cannot directly be compared. A mL is a metric unit of volume equal to one cubic centimeter.
Step-by-step explanation:
In regards to the question of determining the more precise measurement, you need to compare the degrees of accuracy in the measurements given. For example, a measurement of 6 mL is more precise than a measurement of 0.6 mL because it is less precise to have a measurement that extends to the tenth place compared to a whole number which implies a measure only to the nearest mL. In the pair 180 cm and 21 mL, these measurements are not directly comparable as they are units for different types of measurement: one for length and one for volume. Nonetheless, if a liquid volume is measured using a device with 1-mL divisions, it can be measured to the nearest 0.1 mL.
The question regarding the dimensions of an object (6.2 cm × 13.7 cm × 26.9 cm) is related to the interpretation of measurements. To identify the length, one would typically refer to the longest dimension, which in this case is 26.9 cm.
Regarding the size of a milliliter (mL), it is a unit of volume in the metric system equal to one-thousandth of a liter or one cubic centimeter. In applying significant figures to measurements, as in the example provided where the result of a calculation is rounded to two significant figures, you should take into account the precision of the measurements provided. Thus, reading volumes on a graduated cylinder carefully and estimating a tenth of a milliliter is crucial.