# Explanation of symbols

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## Measures and weight

#### Length

 m metre mm millimetre = 0.001 m cm centimetre = 0.01 m km kilometre = 1 000 m mil 10 kilometres = 10 000 m

#### Area

 m2 square metre a are = 100 m2 daa decare = 1 000 m2 ha hectare = 1 0 000 m2 km2 square kilometre = 1 000 000 m2

#### Volume

 m3 cubic metre l, L litre = 0.001 m3 hl, HL hectolitre = 0.1 m3 = 100 l barrel US measure of volume for petroleum = (US) 0.159 m3 = 159 l

#### Mass (Weight)

 kg kilogram t ton = 1 000 kg tkm measure of transport performance = t · km

#### Time

 s second min minute = 60 s h hour = 60 min d day = 24 h

#### Temperature

 ºC degree Celsius

#### Electric current

 A ampere

#### Power

 W watt 1 W =1 J/s = VA kW kilowatt = 1 000 W MW megawatt = 1 000 000 W MVA megavolt ampere = 1 000 000 W

#### Units of measure of ships

 GT Gross ton. The gross tonnage of a ship indicates the volume of the whole ship including superstructure, deck and deck house. NT Net ton. The net tonnage indicates the size of cargo space.

#### Some prefixes

Prefix Symbol Factor
exa E 1018 =1 000 000 000 000 000 000
peta P 1015 =1 000 000 000 000 000
tera T 1012 =1 000 000 000 000
giga G 109 =1 000 000 000
mega M 106 =1 000 000
kilo k 103 =1 000
hekto h 102 =100
deka da 10 =10