This site describes solve-engine as it is on main: 2.43.0, which npm does not have yet. npm installs 2.40.0, so a page may show an answer that version does not give yet.
DERIVED_UNITS_PACKAGE
const DERIVED_UNITS_PACKAGE: IEnginePackage;Defined in: packages/engine/src/packages/derived/DerivedUnitsPackage.ts:55
Named derived units on output (issue #191). Multiplying two compatible
quantities composes their dimensions in the VM (see uom/Dimensions.ts); this
package supplies the as <named unit> readouts and the m/s^2 acceleration
literal. On by default and removable.
The as targets are registered under their own spellings. A name is
matched as typed first, so as mW is milliwatts and as MW megawatts
(issue #824); a spelling that matches none (as n, as KWH) falls back to
the lower-cased name, which reaches the one unit it can mean, and a
lower-cased name two units share (as mw) is refused by name rather than
read as either.