Metric units are way better than the alternatives.
It depends which property you are measuring.
Ounces would be appropriate.
There is really no such thing as a "liquid" unit. The unit of measure is for the VOLUME of something. The best unit for measuring the volume of a human bathtub would be the "Litre".
The appropriate unit is grams.
As far as I am aware, CO is not a unit of measure.
a cup is the best unit to measure the capacity of a small drinking glass
Feet and inches
The best unit to measure the weight of strawberry is kilogram.
The best unit of measurement to measure an alligator is feet.
metre or feet
Meters, or centimeters.