How many?

Millimetres

The millimetre or millimeter is a unit of length in the metric system, equal to one thousandth of a metre. There are one thousand millimetres in a metre. There are ten millimetres in a centimetre. The millimetre is used for measuring thinner things. For example, wooden flooring and underlay is often measured millimetres

Nautical Miles

A nautical mile is a unit of length used in air, marine, and space navigation, and for the definition of territorial waters.Historically, it was defined as the meridian arc length corresponding to one minute (1/60 of a degree) of latitude. Today the international nautical mile is defined as exactly 1,852 metres. The derived unit of speed is the knot, one nautical mile per hour. To sail from Southampton to New York would cover a distance of around 3,081 nautical miles.