mm
The metric unit used for measuring the width of a fingernail is usually millimeters (mm).
Metres, to measure its length or width, square metres to measure its area.
You would use the metric unit "liters" to measure the capacity of a hot water tank.
Meters or feet are commonly used to measure the width of a house.
Because of the dimensions involved, that would be measured in km. (kilometers).
Kilometres
centimetre
The metric unit used for measuring the width of a fingernail is usually millimeters (mm).
Metres, to measure its length or width, square metres to measure its area.
I would go with millimetres
the metric system
The metric unit of the meter would be the appropriate measure of the area of classroom. Calculating area involves multiplying the length (in meters) of the classroom's length and width. Area of the classroom would be in square (^2) meters.
Yards if you work in imperial units or metres if you work in metric units
You would use the metric unit "liters" to measure the capacity of a hot water tank.
Meters or feet are commonly used to measure the width of a house.
Millimetres (or centimetres to one decimal place).
Because of the dimensions involved, that would be measured in km. (kilometers).