Nowadays this is done by flow cytometrie. There are several model organisms that are completely sequenced by now. This means their exact number of total base pairs is known. Additionally the weight of their DNA is known. This means it is possible to correlate the weight of DNA to a number of base pairs. This value of pico grams can indirectly (amount of flourescence) be measured by flow cytometrie.
it is measured in speed because of how fast it can transfer to the screen
The Font is the style and the font size is measured in Points
with a tape measure
Earths diameters is a straight line through the middle of the Earth. That is how the size of planets is measured.
VDU, which stands for Visual Display Unit, is measured in inches. It refers to the size of the screen of a computer monitor or television.
Cell size is measured in nanometers (nm) using a calibrated scale on the microscope objective.
Points
Meters
Pixels.
The size of a laser or electron beam is measured in milliradians. This is because they are subject to divergence.
It is measured in points.
If you mean the screen size, then it is measured by the diagonal of the screen from corner to corner.
diagonal
TEU's
By how big your dick is
it is measured in speed because of how fast it can transfer to the screen
It is the area and is measured in square units.