A comparison.
"Compared to" is used to highlight similarities between two different things. "Compared with" is used to examine the differences between two similar things.
is called an inequality
Ratio or proportion.
Figurative statement is a statement, used in a way, different from the usual meaning.
The two units measure different types of things and can't be directly compared or converted.
it depends on the two different things
useful
50mm squared indicates an areas while inches equals length. These are two different units that can not be compared because they measure different things.
Potential difference is measured in volts. It's a measure of the difference of electrical charge between two points in a circuit. V = J/C = J/A s = kg m2/A s2
Earthquakes and volcanoes are two different things and cannot be compared easily. However, volcanoes can cause earthquakes and vice versa.
The two measure different things and so cannot be compared. It is like asking if a pound is bigger than a foot!