Task: Class Definition Understanding (ontology: Earth_Environment/OBOE)

Which of the following definitions best describes 'Derived Unit'?

A. The the concept (symbol: S) is the SI derived unit of electric conductance and electric admittance. Conductance and admittance are the reciprocals of resistance and impedance respectively, hence one the concept is equal to the reciprocal of one ohm, and is sometimes referred to as the mho. It is named after the German inventor and industrialist Ernst Werner von the concept. In English, the term the concept is used both for the singular and plural. The 14th General Conference on Weights and Measures approved the addition of the the concept as an SI derived unit in 1971.

It is a composite unit in OBOE because it is composed of 2 base units, and OBOE-derived units are a single base unit raised to a power.

a the concept is Ampere/volt
B. A prefixed unit consists of a base unit and a prefix integer value that serves as a multiplier. For example, a centimeter is a prefixed unit that combines a meter base unit and the prefix multiplier 0.01 such that one centimeter is equivalent to 0.01 meters.
C. A the concept raises a base or prefixed unit to an integer power other than 0 or 1. For example, the unit 'square meter' is a unit derived from the 'meter' base unit raised to the power 2. As another example, a 'square centimeter' is a unit derived from the 'centimeter' prefixed unit raised to the power 2.

BRL 20160601: I removed this restriction so that CompositeUnits like XXXPerLiter would not reason to owl:Nothing. hasUnit exactly 1 (BaseUnit or PrefixedUnit)
D. A the concept is a unit that is not naturally decomposed into other units.

Answer: A the concept raises a base or prefixed unit to an integer power other than 0 or 1. For example, the unit 'square meter' is a unit derived from the 'meter' base unit raised to the power 2. As another example, a 'square centimeter' is a unit derived from the 'centimeter' prefixed unit raised to the power 2.

BRL 20160601: I removed this restriction so that CompositeUnits like XXXPerLiter would not reason to owl:Nothing. hasUnit exactly 1 (BaseUnit or PrefixedUnit)