Final answer:
The second biggest advantage of metric prefixes is the ease of conversion between units because the metric system is based on sequential powers of ten, making calculations and scaling across magnitudes simple and consistent.
Step-by-step explanation:
The second biggest advantage of using the metric prefixes over the different units of the U.S. system is ease of conversion between units. Metric systems allow for straightforward conversions because they are based on powers of ten; for instance, converting between centimeters and meters only requires shifting the decimal point. Unlike in the U.S. customary units, where conversions are based on various non-decimal units such as 12 inches in a foot or 5,280 feet in a mile, the metric system is simpler because it utilizes a decimal system where units increase or decrease by powers of ten.
For example, 1 meter is equal to 100 centimeters and 1 kilometer is equal to 1,000 meters. This simplicity allows for easy scaling across large ranges of magnitude without creating new units of measurement. Therefore, whether working with construction, optical design, or air travel, the same base unit with different metric prefixes can be applied conveniently.