Extend the line segment AB to point C so that BC = 2Ab, and extend the line segment Ba to point d so that ad = 1 / 2Ab, then AB: AC=___ ,CD:BD=___

Extend the line segment AB to point C so that BC = 2Ab, and extend the line segment Ba to point d so that ad = 1 / 2Ab, then AB: AC=___ ,CD:BD=___

Extend the line segment AB to point C so that BC = 2Ab, and extend the line segment Ba to point d so that ad = 1 / 2Ab, then AB: AC=___ ,CD:BD=___
D—A——B————C
AB:AC=1/3,
CD:BD=7/3