I would use a tape measure.
I would use a ruler or a tape measure. After I was done, I would express the measurement in centimeters or inches.
A ruler: I have got one right next to me on my desk.
In SI units, use centimeters or meters. In non-SI units, use inches or feet.
They are not. If I say that I have four pens on my desk, my measure of the number of pens on my desk is 4. Not 3.9, nor 4.1. Nor even 4.0000000000000000001 So the question is based on false premises.
feet
Use a protractor.
You would likely use a ruler or a measuring tape.
Tape measure and centimetre.
c m/mm
You would probably measure a keyboard in centimeters (cm).
Use meter sticks to measure the length, width, and height of a lab table or desk in the classroom.
cm
Typically, you measure a desk height with feet and a desk width with feet also. But, it depends on the size.
centimeters or both meter & centimeter
Inches or centimeters, depending on where you live.
I would use a ruler or a tape measure. After I was done, I would express the measurement in centimeters or inches.
Scale and inch-tape can be used to measure desk. It is 1-2 m long.