strong/strongstrong/strong=5,则∣strong/strong∣=( )
①
img class=kfformula src=zzximg/20190809/1565319639836572.png data-latex=5/
②
img class=kfformula src=zzximg/20190809/1565319639607345.png data-latex=25/
③
img class=kfformula src=zzximg/20190809/1565319639359617.png data-latex=\sqrt {5}/
④
img class=kfformula src=zzximg/20190809/1565319639200781.png data-latex=1/