feet or meters
For the United States feet. But for other countries meters.
kilometers
Most likely the metric system of measurement is used. I would assume millimetres would be the most likely measurement between letters.
It depends on what scale you are measuring. If you want to measure the distant between your house and your local supermarket, a ruler will be very accurate (if you use it in a proper way) but if you want to measure the distance between two nuclei of two cells, a ruler will be highly inaccurate.
Kilo Meter is mostly used for use miles to measure.
For the United States feet. But for other countries meters.
Displacement means a measure of distance traveled.
depends on which country you are in...mostly traveling distance is measured in km or miles. 1 mile = 1.6 km
Meter.... or more likely millimeters
Odometer
The answer depends on the tape measure. It is quite likely it is 375 centimetres = 3.75 metres, but it is not possible to be sure.
Kilometers
The measurement is likely to be in feet and inches, or in metres and centimetres.
Most likely the metric system of measurement is used. I would assume millimetres would be the most likely measurement between letters.
kilometers
Kilometers are more likely to be used to measure the distance between two places, rather than the size of objects, since in our normal experience, objects are more likely to be measured by meters or centimeters rather than by kilometers. However, the diameter of planets and their moons, or of the sun or stars, can be measured in kilometers.
cm most likely if you want to be precise. but meters if you are making an estimate.