units
em(`M' の幅), ex(`x' の高さ),
pt(0.351mm), pc(4.2mm), mm, cm, in(25.4mm), sp(0.54
bp(0.353mm), cc(4.51mm), Q(0.25mm), H(0.25mm). zw*, zh*(日本語文字の幅/高さ). \fill
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