(K) The SI unit of temperature.
Definition: One Kelvin is 1/273.16 of the difference between the triple point of water (at exactly 273.16 K) and absolute zero.
The triple point of water is the temperature at which water can exist simultaneously in the gaseous, liquid, and solid states. Absolute zero is the temperature at which all molecular motion discontinues. 0 K is according to -273.15° Celsius and -459° Fahrenheit.

(kg) The base SI unit of mass of the metric system.
Definition: 1 kilogram is defined as the mass of the standard kilogram, a platinum-iridium bar in the custody of the International Bureau of Weights and Measures (BIPM) near Paris, France.
A traditional unit of mass or weight is also the pound (in general use, e.g. in the United States and Great Britain), with the symbol lb (derived from the Latin word libra).

1 kg = 2.204627 pound (lb. av., lbs.)
1 pound (lb. av., lbs.) = 0.453 kg.

Smaller units are, e.g.
1 000 gram (g) = 1 kg
1 000 milligram (mg) = 1 g
1 000 microgram (µg) = 1 mg

(lx) Lux is the SI unit of illumination. Lux is based on lumen, and lumen is a derived unit based on candela. One lux is equal to the intensity of light on a surface that is 1 m from a uniform point source of one candle intensity or equal to one lumen (lm) per square meter.
The formula is:
1 lx = 1 lm/m²

(MeV) 1 Megaelectron volt = 1,000,000 eV

See Electron Volt.

(m) The SI base unit of distance.
Definition: 1983 defined as the distance traveled by light in a vacuum during the time interval of 1/299 792 458 of a second.
The speed of light in a vacuum, c, is one of the fundamental constants of nature.

1 meter (m) is equal to approximately 39.370 079 inches (in)
1 meter is equal to approximately 3.280 840 feet (ft)
1 meter is equal to approximately 1.093 613 3 yard (yd)
1 square meter (m²) is equal to approximately 10.763911 square feet (ft²)
1 inch = 2.54 centimeters
Smaller or larger units are, e.g.:
1 meter (m) = 1 000 millimeter (mm)
1 micrometer (µm) = 10^-6 meter (m)
1 nanometer (nm) = 10^-9 meter (m)
1 picometer (pm) = 10^-12 meter (m)
1 femtometer (fm) = 10^-15 meter (m)
1 kilometer (km) = 1 000 meter (m)
1 kilometer (km) = 0.62137 (statute) miles (mi)

See also System International.