If your measuring it for a science class then you should use a metric measurement, in this case centimeters. If its for a math problem then measure it in whatever units that were given to you in the original problem to make conversions easier. If its for anything else then just use your best judgement.
always the meter to measure length. This is an SI (international) unit of measurment, and is the standard international unit of measurment for length.
the metric system
Length would be the most appropriate unit of measurement
I would use a ruler. After I had completed the measurement, I could describe my findings in any unit of length, but inches or centimeters would most likely produce the most convenient number.
grams or meters weight or length
always the meter to measure length. This is an SI (international) unit of measurment, and is the standard international unit of measurment for length.
Centimeters
A kilometre.
meeters?
Centimeters
Time
a millimeter
Millimetre.
Milligrams
the metric system
Kilometres
The meter.