Nanometer
Every prefix in the metric system denotes a power of 10.
SI prefixes are also known as metric prefixes, and they indicate a multiple of a fraction of a unit. The SI prefix for billion is giga.
I think that you mean Metric unit. The base unit is the Gram. Prefixes are used to modify the unit. For instance, Kilogram, meaning 1000 Grams.
All masses are measured in kilograms, the prefixes show the multiple or fraction of the kilogram. Because the base unit has the prefix kilo, all prefixes are based on the gram, but the base unit is the kilogram.
The unit of mass in the metric system is the gram. You can adjust that with the metric prefixes. A kilogram = 1000 grams, a milligram = 0,001 gram. and so on.
L (Liters). Since its metric, prefixes such as centi-, milli-, deca-, kilo-, etc. denote certain powers of this unit. For example. mL, is commonly used.
The gram is the base unit which prefixes are added (such as milligram or kilogram), but the SI system uses the kilogram as the base unit for mass.
Metric time is the measure of time interval using the metric system, which defines the second as the base unit of time, and multiple and submultiple units formed with metric prefixes, such as kiloseconds and milliseconds.
In the metric systems, unlike other systems, there is only one unit for each measurement; e.g the only unit for length is the metre. For lengths much longer, or shorter, lengths we use prefixes to indicate the fraction or multiple of the metre. For short lengths the fractions are thousandths, millionths, billionths; for which the prefixes are milli-, micro-, and nano-. For longer lengths, the multiples are thousands, millions, and billions; for which the prefixes are kilo-, mega-, and giga-. The prefixes indicate the fraction,or the multiple of the base unit.
The base unit of mass is the kilogram, although the prefixes are, for historical reasons, based on the gram.
The SI unit for volume is cubic metres, because the unit is cubed the normal prefixes can become confusing. So, it is more common to use litres, the normal prefixes apply to litres.