The carob seed which became the modern carats shows how ancient Greeks devised ingenious ways to ensure fairness in trade.

Exercise in sorting and matching abbreviations and units of measure. Entry 3 - Imperial and metric measures in context 1: length Exercise in identifying the contexts in which measures of length ...

The sunflower is 214 cm tall. Calculate the height of the sunflower in metres and millimetres. There are 100 centimetres in a metre. Metres are larger than centimetres so the number of centimetres ...

And he serves on the General Conference on Weights and Measures, the supreme authority that names the units of measure and defines the prefixes that tell you how big they are. His opinion ...

An angstrom (Å) is a unit of length equal to 10-10 meters or 0.1 nanometers. It is named after the Swedish physicist Anders Jonas Ångström, who first used it to measure the wavelengths of light. The ...

A nanometer (nm) is a unit of length in the metric system, defined as one billionth (10-9) of a meter (m). The meter is the base unit of length in the International System of Units (SI), making the ...