Rail gauge is the term used to measure the spacing of the rails on a railway track. This term is used in Australia. In the U.S., we use the term track gauge.

there is track width (measured from mid rail to mid rail) and track gauge (measured from inside rail to inside rail. As that is the most important size of track, that is normally the distances referenced to. normal distance for track gauge is 1435 mm

1.62 mt.

Standard Gauge. 4ft 8"

Depends on the railroad, but the most common was 33 feet lengths - same as standard gauge.