there are many instruments used to measure length . measuring tape is used to measure the length of room.
Meterstick
One could use a ruler.
A tape measure is used in tailoring. A meter with a wheel is used to measure cloth coming off a loom.
The minimum length that a caliper can measure is 0.1 mm. While the minimum length that a micrometer can measure is 0.01 mm. permission; The most commonly used instrument for measuring length is the micrometer.
The instrument "Metalic tap" is generally used for length measurement in India
there are many instruments used to measure length depending upon the size of object , Ruler is Metric instrument used to measure length. Screw gauge is also used as an instrument used to measure length in mm.
mass
Strangely worded question, but a tape measure will measure length.
It is a meterstick!
Meterstick
Vernier Calipers are instruments that are used measure length. It is an instrument that provides a digit of accuracy.
Ruler, meter stick, yard stick
centimeter
A ruler is an example of an instrument that can be used to measure relatively small linear distances, though it could not measure all three at once.
Class room can be measure in Meters easily :)
metric ruler
meter stick