When expressing a range of values with units of measure, only use the units after the second value.
… increased production from 20 to 30%
… had permeabilities of 70 to 100 md
… drilled the section from 3,478 to 4,752 ft
Note that an N-dash can be used: 70–100 md, but don’t mix the from/to method with the N-dash method.
Bad Example: from 20–30%