Final answer:
Units such as kilometer, milligram, and kelvin are part of the SI system, while units like inch, Fahrenheit, ounce, and yard are part of the US customary system.
Step-by-step explanation:
The units provided need to be sorted based on whether they belong to the SI system or the US customary system. The SI system, also known as the International System of Units, is a system of measurement based on the metric system. It uses units such as meters for length, kilograms for mass, and seconds for time, often with metric prefixes like kilo- (1000 units) and milli- (1/1000 of a unit) to scale the base units. By contrast, the US customary system, primarily used in the United States, includes units like inches, feet, pounds, and Fahrenheit.
Sorting the units based on the system they're used in:
- a) SI system: kilometer, milligram, kelvin
- b) US customary system: inch, Fahrenheit, ounce, yard
- c) SI system: kelvin (inch and ounce incorrectly listed and belong to the US customary system)
- d) US customary system: yard (kilometer and milligram incorrectly listed and belong to the SI system)