A balloon is moving up in air vertically above a point A on the ground . When it is  at high  ${\text{h}}_{\text{1}}$ ,a girl standing at a distance d (  point B from A)  (see figure) sees it at an angle ${\text{45}}^0$ with respect to the vertical . When the balloon climbs up a further  height  ${\text{h}}_2$, it is seen at an angle ${\text{60}}^0$  with respect to the vertical if the girl moves further by a distance 2.464d   (Point C) . Then the height ${\text{h}}_2$  is ( Given  ${\text{tan 30}}^0$=0.5774): 

• A

  0.464 d 

• B

  d

• C

  0.732 d

• D

  1.464 d