Is this a riddle?
The best way to measure thickness is to use an ultrasonic transducer. You use the back reflection to figure out the thickness.
Micrometres.
you will use cm because it is useful then the other types of measurement
An ultrasonic thickness gauge is required for measuring the thickness of different types of materials. The best ultrasonic thickness gauge you can buy is the Defelsko Corporation Ultrasonic Thickness gauge.
The best unit for measuring the width of a textbook would likely be centimeters (cm) or inches (in), as these are commonly used units of measurement for smaller objects like books. These units provide a precise measurement that is easy to understand and compare.
The simple way is with a screw micrometer, just put the paper in, do up the jaws with the ratchet and there is your answer. I would measure in a few places and average the results for best accuracy. If you don't happen to have a screw micrometer you could get a rough answer by measuring a stack of paper (say a ream of 500 sheets) with a ruler and dividing the answer by the number of sheets.
Plywood. It has more trapped air.
Pounds
It depends which property you are measuring. For linear dimensions a tape measure would be best
Measure the diameter of the rug, and match it to the floor for best style.
The rate of photosynthesis would be slowed down by increasing the thickness of a leaf. Leaves that are broad and thin offer the best conditions for the process.
What is the purpose of the following sentence?I think it would be best to study the problem carefully.