Why can’t I abbreviate millilitres as ML

It is acceptable to abbreviate litre as ℓ, l, or L in Canada. The official international metric system uses only “l”. The correct abbreviation for “milli” is “m”. The upper case “M” is the abbreviation for “mega”. Where a millilitre is a one thousandth of a litre, a megalitre is one million litres. Use of “ML” for ... ................
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